Google Code-in

Your task is to:

1. Add support for change tagging to the userrights API module.
2. Add support for change tagging to the review API action that is part of the FlaggedRevs extension. In this case, you have to take care with terminology; it might be necessary to use the term "change tags" more extensively, because the FlaggedRevs code uses the word "tags" to refer to an unrelated concept.

This involves adding a new parameter called tags, checking that the user is allowed to apply change tags, and then applying the tags themselves. ApiDelete as of this patch is a good model.