add
Fix for 
Issue 23: QXmppBind compilation error on macosx starting from r23
Issue 26: examples fail to link on macosx and linux
Issue 24: all text files should have the svn property eol-style set

Contributed by: Marco Molteni
make sur examples get rebuilt when the library changes (issue #28)
be consistent, allow debug_and_release throughout the tree
rename QXmppClient.pro to qxmpp, it's confusing
Merge externals/qxmpp
Initial work on XMPP integration.