check if autocommit is enabled for the database, and skip commit if 'yes'

[mloyanich]

PorstgreSQL database throws an error, when you try calling commit() when the autocommit is enabled: sqlalchemy.exc.DatabaseError: (jaydebeapi.DatabaseError) org.postgresql.util.PSQLException: Cannot commit when autoCommit is enabled.

Regular psycopg2 driver ignores the commit if there is nothing to commit (which would be true in case transactions were autocommited)

Could we add the functionality to skip commit in case jconn.getAutoCommit() == True?