switch from GnuPGInterface to python-gnupg, so gpg is available under windows. Fixes #5096, #3615, #1890, #996

Also use sed to remove now unneeded Vim lines, 2to3 -f ws_comma to fix
some whitespace, and fix some other madness manually.

also use 2to3 -f ws_comma to fix some whitespace

holy diff batman!

Plan is to move our ConnectionX classess to the protocol package one by one. Each move should be more than a simple copy paste. It should be preceeded by cleanups and the like.

better compliance to the last version of XEP 0166, 0167 and 0176

 * add a checkbutton to use the entered nickname by default without asking anymore. Fixes #5141

[Spike411] Facebook iconset for Gajim. A great thanks to Jakub Szypulka for is iconset: http://cubestuff.wordpress.com/2008/05/21/facebook-goes-tango/

[roidelapluie] Added initial support for Roster Item Exchange (XEP-0144) based on ticket #378. Only handling NS_ROSTERX 'set' operations is supported and tested as of now.