Updated to support Grunt 0.4.0rc5

This adds support for Grunt 0.4.0rc5.

- Removed references to expandFiles (https://github.com/gruntjs/grunt/commit/b60907b7b07065a41325cd8a185d1a478b69f25a)

Extra:
- Clean task would fail if test/tmp did not exist. Now run mdkir before cleaning.