Tweaked the OAuth /authorize UI and made other cleanups

* Convert the HTML form to a jQuery UI dialog when possible
* Added $wgMWOAuthGrantPermissionGroups for grouping grants on the
  /authorize page. This also hides the "basic rights" grant from
  said page.
* Cleaned up module names and changed some addModules() calls to
  use addModuleStyles().
* Also remove oversight grants per privacy policy

Change-Id: I694f68a85f3efa7871ea4aa1b629f56a069f126a
Merge "Tweaked the OAuth /authorize UI and made other cleanups"