- gps info added if available

Still to do: signal handler for sigint/quit/term

Problems so far:
* leaks zombie processes
* does not work when terminating feh with a signal (since the convert process
  is no longer in feh's process group)

commit 9c8226a1
Merge: e4483e5e 132ecc0f
Author: Dennis Real <github@tildepipe.org>
Date:   Sun Feb 5 17:24:17 2012 +0100

    Merge branch 'master' of ssh://github.com/reald/feh

commit e4483e5e
Author: Dennis Real <github@tildepipe.org>
Date:   Sun Feb 5 16:56:29 2012 +0100

    - improved handling of images which have exif tags but not ours
    - fixed uninitialized pointer in thumbnail mode
    - added nikon lens info if available

commit 132ecc0f
Author: Dennis Real <github@tildepipe.org>
Date:   Sun Feb 5 16:56:29 2012 +0100

    - improved handling of images which have exif tags but not ours
    - fixed uninitialzed pointer in thumbnail mode
    - added nikon lens info if available

- fixed uninitialized pointer in thumbnail mode
- added nikon lens info if available

- fixed uninitialzed pointer in thumbnail mode
- added nikon lens info if available

Required e.g. for feh --preload --thumbnails

This fixes a "memory leak" (though strictly speaking it is none) when using
feh --reload on http URLs.

fixes valgrind warning about use of uninitialized values

This reverts commit 8b79bc33.

This fixes a segfault in --reload when the image becomes unloadable while feh
is running.

Note that this does not affect --reload with more than one file: If the
current image is removed, feh will simply jump to the next image. feh will
only quit if the file still exists, but can no longer be loaded.

feh_draw_info used to iterate line-wise over the info output, but now we need
to cache it somewhere to get the length of the longest line.

The info text used to be located 2px away from the bottom / left edges.  Now
that --draw-tinted has been implemented, that leaves us with an ugly edge, so
move it directly to the edge.

By default, feh draws white text with a black drop-shadow, which is well
readable in most, but not all cases.  The --draw-tinted option draws a
semi-transparent black box around all texts.  This improves readability, but
does not look as nice, so it won't become default behaviour.

It was suggested to use #7f7f7f7f for the background, but I decided that
for small images surrounded by a black border.

feh_draw_info used to unconditionally swallow the last character of a line,
assuming that it must be a newline. However, the very last line of a program's
output may not end in a newline, in which case its last output character was
omitted.