Fuller Review Board Integration

Tighter integration with Review Board. For example:

• Starting merge request from UI would automatically post review request to RB and RB UI is opened in a separate browser window
• If users try to add a note to pending merge request UI would automatically update review request in RB and RB UI is opened in a separate browser window
• User gets a message if he tries to complete a push and RB review is still open
• After completing the push, users should have a way of knowing which particular review is associated with the push, for example via pop-up when mouse is hovering over the commit link.