Change package.json Chalk version prefix from hat to squiggly, update ...

The Travis builds for 0.6 and 0.8 have been broken since Chalk was added with a caret in the version.  Travis-CI uses npm v1.1.37 for node 0.6, and npm v1.2.30 for node 0.8.  `node-semver` introduced the caret in `v2.1.0`, `npm` didn't pick it up until `v1.3.7`.

Also added Travis build for node 0.10.

*NOTE: This is just a re-issue of v0.2.8 - so I didn't think a new version was needed - and should be published to npmjs.org.*