output paths - make sure directories are made

[PeterDSteinberg]

Fixes #279 . Directories were not being created. Now this works:

python Python/ogusa/scripts/postprocess.py

[PeterDSteinberg]

Don't merge yet - this needs a little work.

[PeterDSteinberg]

EDIT: Was running from wrong test directory

Locally, @jdebacker I am getting:

    def get_resource_stream(self, manager, resource_name):
>       return open(self._fn(self.module_path, resource_name), 'rb')
E       IOError: [Errno 2] No such file or directory: '/Users/psteinberg/miniconda3-4.1.11/envs/py27d/lib/python2.7/site-packages/ogusa-9.99.999+33.g5638ed9.dirty-py2.7.egg/TxFuncEst_policy.pkl'

in

py.test test_parameters.py

[jdebacker]

@PeterDSteinberg this is looking good to me. Let me know when it can be merged.