* libgimp/gimpexport.c: implemented the changes Nick Lamb
suggested:  If the background layer has no alpha channel,
suggest "Flatten" instead of "Merge Visible Layers".

* app/fileops.c: In the MRU list and the doc_index always store
the absolute path to images, so you can open files from the
command-line and gimp will find them later if started from another
dir. Added tooltips that show the full path.

* app/menus.c: fixed a memleak (list entries were not freed on
removal from the MRU list).

* app/main.c
* app/user_install.[ch]: renamed functions and variables to match
the new filename.


--Sven