Update rainbow from 2.1.0 to 2.2.2.
Adds support for Ruby 2.4, no breaking changes.
Changelog: https://github.com/sickill/rainbow/blob/master/Changelog.md#222-2017-04-21
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Adds support for Ruby 2.4, no breaking changes.
Changelog: https://github.com/sickill/rainbow/blob/master/Changelog.md#222-2017-04-21