Sifter support appears.
An clarifying comment.
Updated the Sifter service docs.
Merge branch 'sifter' of github.com:nextupdate/github-services into sifter
fix pull_request_review_comment of irc service
define pull_request_number
Adding initial Apropos hook. Fixing some events.
Moving to new HttpPost base.
Add issues.
added PhraseApp hook
Fixed inheritance: Service now inherits from HTTPPost
Merge pull request #629 from nextupdate/sifter

Add support for Sifter
put all of the instructions in a single place: CONTRIBUTING.md
Merge pull request #628 from hawatian/master

Add Support for Apropos
Merge pull request #632 from docstun/master

Add PhraseApp Service Hook
Merge remote-tracking branch 'soh355/feature/fix-pull-request-review-comment'

Conflicts:
	lib/service/events/pull_request_review_comment_helpers.rb