Merge branch 'segfaultScandirFree' of https://github.com/vorburger/feh into vorburger-segfaultScandirFree

This means it will be treated like an HTTP image (no write operations,
copying to /tmp etc), but it's still better than no file:// support.

Also, this is why it's not documented yet.

Overloads the --geometry option for wallpaper setting
Currently only supports the two options that result in
black borders, --bg-max and --bg-center.

For both, if a geometry offset is specified (w/h is ignored),
the image will be offset the specified pixels from the screen edge
Left side for + numbers, right side for -.
+/-0 will align at the edge of the screen.

From the XChangeProperty man page:
"If the specified format is 32, the property data must be a long array."

Add %L format code (temporary copy of filelist)