fixed default grunt task loop.

Changed the watch task name in the grunt config. It matches now the default. 
If not, then when I executed just "grunt" it was producing errors:



Running "watch:hint" (watch) task
Waiting...Verifying property watch.hint.files exists in config...ERROR
>> Unable to process task.
Warning: Required config property "watch.hint.files" missing.

and eventually ending with:

(node) warning: Recursive process.nextTick detected. This will break in the next version of node. Please use setImmediate for recursive deferral.