Ignore IntelliJ IDEA project files
No more need to install grunt-cli globally

Running grunt cli:
> ./grunt build
Default grunt task is 'build'

Running the default task:
> ./grunt
Optimized js goes to dist
Gruntfile is written in CoffeeScript (like other sources)
Clean before build
Lock down latest dependency versions, also transitive

See https://npmjs.org/doc/shrinkwrap.html
Merge pull request #63 from mileskin/master

Improve build and dependency version handling