Issue #1135480 by lyricnz, drewish: Need to rebuild menus after changing files directory path or download method.

#374202 by (the extremly patience) mikeytown2: Add actions for flushing and generating derivatives of images in filefields on a node.

#241541 by florian.cathala, yingtho, kndr, drewish: Add parameter to imagecache_create_url() and theme_imagecache() to generate relative URLs.

#518980 by iva2k: imagecache_preset_delete() calls imagecache_preset_flush() with id instead of preset array.

Follow up on #381726 and fix a missed bit of the patch.