Add a `query()` classmethod to the `Document` class.
Add a `query()` classmethod to the `Document` class.

--HG--
extra : convert_revision : svn%3A7a298fb0-333a-0410-83e7-658617cd9cf3/trunk%4057

djc/couchdb-python,djc/couchdb-python,infinit/couchdb-python,Roger/couchdb-python