Fixes a problem where adding contacts to newly created group is impossible. Fixes a problem with moving contacts to group and double contact entry shown. Renames protocol groups when meta group is renamed and fixed its storing.
Changes tests as metacontactlist behaviour has changed, now proto-groups also get renamed.
Tries to fix scroll going to top problem in chat window.
Disables send file button when in a group chat. 
Commits work in progress on fixing leaks of every CallDialog and ChatWindow.
Improves DTMF configuration (auto, RTP, SIP INFO or INBAND). Creates a common interface for starting and stopping (RTP or INBAND) DTMF tones into AudioMediaStream interface and its implementation. Reverting DtmfTransformEngine to use previous threaded DTMFDispatcher.