Adding grunt command line globally

Adding grunt command line because Travis can't find grunt
Merge pull request #2565 from SergioCrisostomo/moo_master

Adding grunt command line globally
Update sauce creds on travis so tests run on mootools-core remote.
Merge pull request #2566 from GCheung55/travis-sauce-creds

Update sauce creds on travis so tests run on mootools-core remote.
Let's try this again.
Fixing SL creds again.