Fix another case where filters for counting/listing were wrongly applied
Add method for deleting an actual PermissionGrant directly.
Use Jackson (1.9+) annotation-derived serializing/deserializing to
save some pain with dumping/loading the permission structures. The
permission-querying methods also now send streaming responses. This
was mostly an unsuccessful attempt to fix the intermittant socket
closed errors that seems to afflict only the AccessResource and the
PermissionResource, which both happen to Json-structure bodies which
we parse with Jackson. More investigating needed here.