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."

Sort filelist by modification time, newer files first. Useful for
perusing a directory of images by most recently added or changed.

Patch by sdaau on IRC. Thanks!

- ISO
- Whitebalance
- PictureControlData
- Flash output power

Previously feh would set a black background around wallpaper images,
with no option to change.

This commit extends the functionality offered by the --image-bg option,
which is available for regular image viewing, to centered and max'ed feh
backgrounds. Essentially, this means a white border can now be chosen
in addition to a black one.