Update src, deps, and tests for 0.8-0.10

Hi there!

I removed the deprecated use of `path.exists` and `path.existsSync`, updated the dependancies ( vows wouldn't work in 0.10.x ), and cleaned up the tests. Just general maintenance for the higher versions of node.

Unfortunately, this is a breaking change...and will not work with  <= 0.6 any longer. I bumped the version to 0.2.0 to reflect the breakage. Perhaps there is a workaround, and if you are interested in keeping 0.4 and 0.6 versions, I can think on how to do this. But I think most people expect this.


Let me know if I can change anything or present the pull request differently.

- rooftopsparrow