Create Version 2 of the Humbug Hook Payload, Rename Humbug->Zulip

This adds additional fields to help users customize where their github
traffic ends up, and helps filter the traffic for particularly noisy
repositories.

This also rebrands the Humbug hook as Zulip, to reflect the change
in Company name.
Revise Zulip documentation
Fixup Humbug/Zulip unit test
First commit
set the correct class name
changed some URLs
minor URL edits
Create service for Pushbullet.
Added documentation for Pushbullet.
Trim trailing whitespace.
Add test for Pushbullet service.
Use helpers
Update tests.
add support for HipChat message colors

see: https://www.hipchat.com/docs/api/method/rooms/message
Add MyGet service

Add www.myget.org service
Update myget_test.rb
Adding Leanpub service
Update leanpub_test.rb

It's LeanpubTest, not LeanpubText
Update myget.rb
Merge pull request #805 from myget/master

Add MyGet service