Squashed commit of the following:

commit 55e66e15af898f4c01d7d265013124fefce795e4
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 19:59:46 2011 +0200

    Save all filenames in ~/.fehbg

commit afc2774f315fc379aa96de58decf8370772036af
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 19:24:38 2011 +0200

    Update test/bg --bg-fill images (off-by-one due to changed implementation)

commit bd4210cff2e895414df12868f6cab7f193c5adf5
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 14:47:00 2011 +0200

    Fix feh_wm_set_bg_maxed

commit d9ada9dc2a74aef6ae0924e9c0ff296b94ee25bc
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 14:39:11 2011 +0200

    Fix for non-xinerama setups

commit be2cf0f1f8c00b737e7141a372d3cbc9db4c949f
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 14:24:44 2011 +0200

    Move wallpaper calculation code into separate functions

commit 4e07c1f9734569fdd778a813c5a85c63b51b3175
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 13:01:46 2011 +0200

    Remove unnecessary temporary variable

commit 23d1d733b21d1560e1fbcadddc34cae3d666b21d
Author: Daniel Friesel <derf@finalrewind.org>
Date:   Mon Sep 26 12:46:25 2011 +0200

    Initial conversion, works with --bg-scale

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

This was broken by the changes allowing --reload to retry ad infinitum.

Now force_new is used to decide whether or not to work around the Imlib2
caching issue.  Because of this, a few feh_reload_image calls needed to be
changed.

fixes valgrind warning about use of uninitialized values

Patch by livibetter

This commit removes the feh_file_remove_from_list call from feh_reload_image.
We can safely do this because if the file itself was removed, cb_reload_timer
will take care of updating the filelist, and in all other cases it is intended
to leave the image in the filelist and retry.

A warning will be displayed in the image if the reload failed.

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.

This fixes half of the issue - windows on Xinerama screen 0 no longer become
too large, but the bug still appears on the other screens (unless
XINERAMA_SCREEN is set)

* remove unused variable Im1 in filelist.c
* options are initialised as 0, so only explicitly set those to 0 for which it
  makes sense because of their context
* Make a few warnings about wrong option combinations fatal

Most screenshot-based webcams are no longer around, and I don't think the few
remaining ones need the feh-cam tool.  Unless I get lots of mails from people
still using it, of course.

Note that read_filelist used to check if its argument was an image (for people
accidentaly typing "feh -df *" instead of "feh -dF *"); this was removed
because it failed on /dev/stdin.

I might re-add it, but I'm not yet sure about the future of feh's automatic
filelist saving.