Update bower.json to avoid error on "bower install" command

While we wait for the bower team to rename the lesshat component in their database (see requests at https://github.com/bower/bower/issues/120#issuecomment-27586470 and https://github.com/bower/bower/issues/953), this change makes an explicit reference to the lesshat repo.
Merge pull request #63 from hal-gh/patch-3

Explicitly set lesshat bower path to its Github repo. Bower registry is temporarily broken.