Adds query result auxiliary objects

**Adds** ``query.results.auxiliary``, which contains two attributes ``authors`` and ``types``. The ``authors`` attribute is a list of author info objects which can be input into a backbone.Collection with little effort.

**Removes** the ``meta`` key/attribute from the ``query.results.limits`` entries. Everything that was in the meta bit has been moved to full objects in ``query.results.auxiliary``.

**Changes** the value of the type limit in ``query.results.limits``. So what was once 'Book' is now the mimetype for the book/collection value.