If the connection is sync, notices will be processed by pq_fetch()
downstream.
If the connection is async, here we have only sent the query: no result
is ready yet, and neither notices have had a chance to arrive: they will
be retrieved later by pq_is_busy().
Added tests to check the above statement don't break.
* tests/*.py: use the DSN constructed in tests/__init__.py.
* tests/__init__.py: allow setting the host, port and user for the
DSN used by the tests through the environment.
the Connection and Cursor "closed" attributes.
* psycopg/cursor_type.c (psyco_curs_get_closed): add a "closed"
attribute to cursors. It will be True if either the cursor or its
associated connection are closed. This fixes bug #164.
