Option to remove colors in Protractor output.

See angular/protractor#284 and angular/protractor#285 for more info.

There is a standard grunt flag `--no-color` but this doesn't seem to affect protractor.
With this change you can add `noColor: grunt.option('no-color')` to your gruntfile and then it works for protractor too.

I don't know if this is the best solution, but it works and I could really use this feature.

Thanks!