- add workaround to setup.py to avoid setuptools issue regarding multiprocessing

- add workaround to setup.py to avoid setuptools issue regarding multiprocessing
when "setup.py test" is run, #96
- add version detection for 0.8, apply this version detection to
test_autogenerate:AutogenRenderTest.test_render_fk_constraint_kwarg
and emit explicit append_constraint() for each FK if not on 0.8 as FKs
do not auto-attach in 0.7, #96
- add a README containing instructions for running tests and setting up
optional database backens, #96