jshint: ignore libs/jquery.qtip.js

That is a third party library. Will let us have Jenkins pass jshint on
the repository.

Bug: 61609
Change-Id: I62d4880d09e1bea804c4b21d8f84c73b06420cdf
Provide default jshintrc file

Make sure we use sane defaults.

Bug: 61609
Change-Id: Ie0fdb310f9df5a03f9a0f33cd117bbc6addfac23