Make Hipchat messages more concise

Currently, messages posted to hipchat are

Joe User committed to 1 branch at Project/Repository
On branch "master"

• Commit message here and truncate... (a0b1c243)

This means 3 lines per commit, which can easily cause conversations to get lost in the noise. We had this with our previous use of subversion (in that case, posting the entire multi-line commit message), and changing to just post the first line with a link to the web viewer made a remarkable difference.

I know this seems very trivial, but it's relatively easy and makes the experience that much nicer.

Therefore, I'd propose the template changes based on context.

Single commit to 1 branch:

Single line in hipchat.

Joe User committed to branch "master" at Project/Repository: Commit message here and truncate... (a0b1c243)

Multiple commits to 1 branch:

Line per commit, plus header

Joe User committed to branch "master" at Project/Repository

• Commit message here and truncate... (a0b1c243)
• Second commit message... (b30c72c8)

Multiple commits to >1 branch:

Basically, just as-is:

Joe User committed to 2 branches at Project/Repository
On branch "master"

• Commit message here and truncate... (a0b1c243)
• Second commit message... (b30c72c8)

On branch "1.0"

• Another commit message... (c94fe7c6)