Py-august

- doorsense in "init" state is now handled (36 by bdraco)
- API calls resulted in HTTP error throws `AugustApiHTTPError` instead of `HTTPError` (35 by bdraco)

- added the battery level for doorbells (34 by bdraco)
- added bridge and door sense info to lock detail when present (33 by bdraco)

- added missing python-dateutil to setup.py (32 by bdraco)
- added more documentation and constants (31 by bdraco)

- Added support for onetouchlock 28
- Added support for doorsense to the activity module 29
- Fixed refresh token timezone inconsistency 30

Thanks bdraco for all the work above!

- refactored pin.py by changing from camel case to snake case (02d62a8f127ce5ef47d971c5cc5d46f8f37b930b)

- Check auth token expired or not (https://github.com/snjoetw/py-august/pull/15)
- Add example Api usage to the README (https://github.com/snjoetw/py-august/pull/17)