This commit add *.db to .gitignore to ignore the files for testing. We
don't need to track such files.
Change-Id: If2cdc7169453c46324d0f6e100448b07b9ffd68c
This commit switches to use stestr instead of os-testr. It should be
better to reduce the test runner complexity.
Change-Id: Ia16ad5ed6d9ed7be9dc6902f875b0144b24a938a