This fixes the following mandoc warnings.

  man -Tlint feh

  WARNING: skipping empty macro: No

  skipping empty macro
    (mdoc) The indicated macro has no arguments and hence no effect.

  man: /tmp/man1/feh.1:16:14: WARNING: skipping empty macro: No
  man: /tmp/man1/feh.1:16:34: WARNING: skipping empty macro: No
  man: /tmp/man1/feh.1:179:2: WARNING: skipping empty macro: No
  man: /tmp/man1/feh.1:387:48: WARNING: skipping empty macro: No
  man: /tmp/man1/feh.1:785:26: WARNING: skipping empty macro: No
  man: /tmp/man1/feh.1:785:38: WARNING: skipping empty macro: No
  man: /tmp/man1/feh.1:823:26: WARNING: skipping empty macro: No

This fixes many warnings shown by mandoc lint feature and should also respect
the 80 col limit.

  man -Tlint feh

  WARNING: new sentence, new line

  new sentence, new line
    (mdoc) A new sentence starts in the middle of a text line. Start it on a new
    input line to help formatters produce correct spacing.

man: /usr/man/man1/feh.1.gz:35:32: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:78:33: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:90:50: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:95:53: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:97:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:108:17: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:112:36: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:115:24: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:122:20: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:129:21: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:130:9: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:135:19: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:146:64: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:148:43: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:149:58: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:167:2: WARNING: skipping empty macro: No
man: /usr/man/man1/feh.1.gz:175:21: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:177:30: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:178:19: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:186:42: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:189:15: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:199:49: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:213:6: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:227:47: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:231:19: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:242:11: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:274:66: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:285:19: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:297:9: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:311:19: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:340:21: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:351:14: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:360:69: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:365:44: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:372:35: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:395:21: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:396:16: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:397:31: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:406:65: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:407:53: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:430:11: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:440:24: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:442:11: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:447:24: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:455:10: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:458:22: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:491:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:492:44: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:493:42: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:498:26: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:511:59: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:512:55: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:530:18: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:531:46: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:532:24: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:533:41: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:538:50: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:545:13: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:562:11: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:569:41: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:576:26: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:584:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:607:49: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:616:61: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:617:76: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:623:61: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:635:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:638:27: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:640:37: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:650:17: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:666:37: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:677:42: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:682:20: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:683:8: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:688:24: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:703:51: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:714:37: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:728:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:729:44: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:738:61: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:775:34: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:778:42: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:787:36: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:822:19: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:823:22: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:852:46: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:868:26: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:881:10: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:889:10: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:902:43: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:920:65: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:934:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:954:69: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:965:37: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:973:65: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:987:17: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1027:29: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1056:17: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1143:28: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1164:38: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1171:49: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1240:54: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1271:58: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1289:22: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1291:57: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1292:59: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1293:53: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1318:32: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1329:35: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1335:13: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1341:18: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1349:22: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1358:24: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1391:44: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1398:25: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1399:8: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1405:67: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1408:23: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1569:22: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1680:21: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1681:70: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1683:22: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1708:55: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1723:36: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1742:54: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1743:45: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1771:67: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1816:35: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1822:14: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1845:47: WARNING: new sentence, new line
man: /usr/man/man1/feh.1.gz:1902:56: WARNING: new sentence, new line

Fixes non-random behaviour when randomizing file lists several times per
second.

Closes #349

See #278

Closes #386

Merge branch 'fix-toggle-fixed-geometry' of https://github.com/ulteq/feh into ulteq-fix-toggle-fixed-geometry

Closes #272

Closes #367

Closes #218

Merge branch 'fix-no-files-found-on-reload' of https://github.com/Ferada/feh into Ferada-fix-no-files-found-on-reload

Merge branch 'custom-background-color' of https://github.com/ulteq/feh into ulteq-custom-background-color

Closes: #382, #384

This introduces a new feh_should_ignore_image function which is called
at appropriate places in those modes to skip images which are loadable but
undesired.

Merge branch 'dimension-pruning-without-preload' of https://github.com/ulteq/feh into ulteq-dimension-pruning-without-preload