Duplicate sbt-less and rename it to sbt-sass

Bumped version to 0.7-SNAPSHOT
Sorted out the Graph and SassSource files
Adds the necessary parts of the sass-3.2.14 gem
Updates and removes some dependencies
Ties together all the sass parts and adds a scripted test
Merge branch 'feature/sbt-sass' into develop
Fix  a misspelling in the sass version in SassKeys
Improves the importRegex to better match Sass’ import conventions
Had to switch from string to file based Sass compiling to get all the imports correct
Merge pull request #48 from pengerno/develop

Adds a sbt-sass plugin