Removed default ingest menu, ingest configuration can now take a object.

Was not in use and excepting any parameters for the ingest process via GET
was not very safe.

Also the ingest configuration can now take an NewFedoraObject rather than
building one from the configuration options. The old way is still supported
for now though.
Added a new function islandora_user_access() to simplify access callbacks.

This function will check the given object/datastream against the given
permissions and required content models using the given user. If no user is
given the user identified by the GET token will be used, if no token is present
the global user will be used.