Ensure 1:1 mapping between tasks and git commands

[rubenv]

Tasks to check:

• archive
• checkout
• clean
• clone
• commit
• merge
• pull
• push
• rebase
• reset
• stash
• tag

This is related to the discussion in #38. Each command needs to be checked before we can release the first 0.3 release.

Things to look out for:

• Does the grunt task do the same thing as the git command?
• Do the options work as the git task?

Ideally you'd only need to know how to use the git command: converting that command to a grunt configuration should be trivial.

Anyone who wants: feel free to jump in!

[rubenv]

@dylancwood I pulled add out of commit. This pretty much opens the door to release a new major version (I'm thinking of calling it 1.0.0). Anything else should include?