Setup code for auto-config sample generation

Sync in the oslo code for auto-config sample generation and
make the appropriate changes to setup to allow for automatic
option discovery.

`test-requirements.txt` now includes stevedore to
ensure the oslo libraries can all be loaded as expected.

Change-Id: Ieca0aea4d3c67b930c12467317d2f4d83763b601
Merge "Setup code for auto-config sample generation"