Added new and missing tests of the RsItems.
Added new notifier on channel changes.
Reworked fill of channels in ChannelFeed. Now the channel tree is updated and not refilled.
Show unread message count in channels tree.
Fixed memory leak in context menu.
Show a new tray icon and action icon in MainWindow, when new channel messages are available.
Recompile of the GUI needed.
git-svn-id: http://svn.code.sf.net/p/retroshare/code/trunk@3626 b45a01b8-16f6-495d-af2f-9b41ad6348cc
