Acceptance test for postgres
Added comment to postgres doc explaining where the tests are
Removed submission note
Addressed review comment: Removed unnecessary variables
Replace Psycopg2 with pg800
Added pg8000 to setup.py
Addressed review comment: Look out for ProgrammingError
Fixed flake8 issue
Merge pull request #997 from ClusterHQ/postgres-test-FLOC-1042

[FLOC-1042] PostgreSQL Acceptance test