cleanup Gruntfile
refactor variables for use in multiple steps
feature (github release) add support for creating github releases from tag
add superagent as dependency
docs (add Github releases)
change github repo back to grunt-release for actual releases
refactor (github release) print success message when using --no-write option
release 0.6.0
User-Agent is required by Github's API.

I've used grunt-release as value, this is something Github uses in case of problems, as documented here http://developer.github.com/v3/#user-agent-required
Insert missing commas into example options

Discovered, ironically, by me trying to `js2coffee` them.
Merge pull request #60 from lazywithclass/adding-user-agent

User-Agent is required by Github's API.
Merge pull request #62 from searls/patch-1

Insert missing commas into example options
release 0.6.1
add q dependency
significant refactor: use promises, fail loudly, consistent logs
(test) disable push option during tests
release 0.7.0
update docs
Merge upstream grunt-release in hopes to fix larger issues