Rename launchpad parameter to group

In anticipation of storyboard, which has project groups, support
a field called 'group' for each project, which will match that project
to the appropriate group. For launchpad, use group designation as a
mapping to the bug tracker, if it is different.

Change-Id: Ied726fece9f32b8417e18c50ad52ae9279778399
Merge "Rename launchpad parameter to group"