Visualize in which revisions a merged change is included

Introduced a new "Included in" panel on merged changes. The panel
will produce sorted lists all branches and tags which contains the
merged change.

Provides a simple way for users to determine in which revisions of
the project the change is included.

Change-Id: If94b2604607f53a2e45330b56d55cc5de8288054
9 files changed