Clean up HipChat CI notifications

[timothyb89]

Right now our HipChat notifications are very noisy. As an example, we just merged monasca/monasca-docker#322. This caused:

• 2 notifications on the initial commit for both travis events passing (push, pr)
• 2 notifications for another commit (push, pr)
• 1 notification on merge (push)
• 2 notifications for commit to monasca-helm (push, pr)
• 1 notification for merge to monasca-helm
• 1 notification for GitHub pages status update
• 1 notification for auto-update PR to monasca-helm/monasca
• 1 notification (pr) for Travis status update to monasca-helm for auto-update PR (no push since the bot commits to a fork)

So 1 change through the pipeline generated 11 notification cards in our HipChat room.

Issues with this include:

• the bot didn't auto-update the kafka-init module due to New module detection during soft updates #14 - so actually it should've been 12 notifications!
• there are more notifications than anyone will ever actually read
• messages for commits (excluding merge) are missing the PR number (we need Keep track of PR commit hashes #8 to fix this)
• the HipChat card titles are not helpful ("The Travis CI build passed") - should really be the repo name, PR number, and title
• we can probably just discard push events (continuous-integration/travis-ci/push context)
• merge messages and follow-ups are semi-duplicates, maybe we could merge these or just drop merge messages?

Minimally I'd like to see the following messages:

• 1 message for initial commit passing
• 1 message per followup commit passing
• 1 message on merge
• 1 message per followup action
  • should actually be informative, not something useless like "GitHub pages finished building"
  • e.g. "auto-update made to ..." or "release published ..."

It would also be nice to use collapsed cards for all non-error messages. Link directly to the PR via the title and keep the details hidden.

For the above example this would cut it down to 8-9 messages. To be honest this is still too many, but I'm not sure how to cut this down more. At least we can make the messages we do send actually helpful so there's a reason to read them.