Extensions to allow running all appropriate unittests from `Bitten-Slave` distribution: * Include all the runnable test packages * Include `bitten.util.loc` - all `bitten.util` submodules should be included as `bitten.build` steps depend on them * Specify `test_suite` as `bitten.slave_tests` * Add ` unittest` distutils command * Adjust `MANIFEST-SLAVE.in` to include all neccessary modules (including `setup.py` as `setup-slave.py` now depends on it