Disable Checkstyle reporter of JSHint

The Checkstyle reporter made things worse, not better.
Instead of visualising the data in an easy way it hid the data
behind lots of pages, full of irrelevant data and invalid error
messages.

- Categorised things as "High priority" which is a hack for
  Checkstyle that has nothing to do with how JSHint otherwise
  outputs it.
- Caused bug 46066.
- Hid data behind a lot of doors:
  Job page > Checkstyle repot > High priority > Details
  full of "No description available, No description available, .."

No, just give me the plain text reporter without any mess.

Change-Id: I29218fd9786c63eb60617ea66f8637fcd97e9937