Remove deprecated usage of Encoding key in the other desktop file

Oops, I forgot the other one in my rush :/
Merge pull request #131 from rworkman/rworkman

Remove deprecated usage of Encoding key in the other desktop file
Move some non-themed icons to pixmaps/ directory

* Add PIXMAP_PATH to constants
* Add PIXMAP_PATH to icon search path in Functions.py
* Add data/icons/pixmaps/ directory
* Move some icons to $datadir/pixmaps/blueman/
* Add pixmaps stuff to configure.ac