Stand up CallEstablishView by partly cloning CallOfferView
Make TextChatView only reveal itself when in the 'ongoing' state
Tiny refactoring of offerWindow CSS to make it apply to all windows of class 'pending'
Implement the End Call button
Teach the CallView to show itself in ongoing rather than pending
Make default CallEstablish verbiage less awkware
Merge pull request #130 from dmose/call-establish-view

Call establish view