Adds slack adapter
Uses renamed slack API gem
Adds missing chat service registration for slack
Fixes post message method argument order
Change room id to string. Database changes are following later
Includes build data in message options for chat services to display additional information
Adaptes to slack.rb v0.0.5
Adds attachments to Slack adapter to give the message a nicer touch
Adds new settings JANKY_CHAT_SLACK_USERNAME and JANKY_CHAT_SLACK_ICON_URL
Uses slack.rb attachment struct
Uses room name for slack notifications

Conflicts:
	lib/janky/chat_service/slack.rb
Handles string and integer room ids
Merge pull request #205 from netflower/slack-adapter

Add support for Slack