A few tests use u'' unicode literals which are not
supported in Python versions 3.1 and 3.2.

cannot find meaning of this anywhere in Postgresql documentation) seems to work

Support for Postgres range types.

- for the moment, put a catch in it to see if we can trap that issue
on jenkins

One can use this to emit statements, which can not be
executed within a transaction (e. g. CREATE DATABASE):

    from sqlalchemy import create_engine

    eng = create_engine('postgresql://test:test@localhost/test')

    conn = eng.connect().execution_options(isolation_level='AUTOCOMMIT')
    conn.execute('CREATE DATABASE test2;')

Fixes issue #2072.