Package.json improvements

* Bump version
* Add (::) to the description
* Add coffeescript to the keywords
* Move sweet.js to the devDependencies
* Allow sweet.js devDependency to be any of the v.0.4.x branch.
Add index property to package.json pointing to macro
Move coco.js to coco.sjs
main field, not index, for where sjs/node look
Merge pull request #3 from Havvy/master

To make the package usable.