* Add doctests to SmartBulb
* Add SmartDevice doctests, cleanup README.md
* add doctests for smartplug and smartstrip
* add discover doctests
* Fix bulb mock
* add smartdimmer doctests
* add sphinx-generated docs, cleanup readme a bit
* remove sphinx-click as it does not work with asyncclick
* in preparation for rtd hooking, move doc deps to be separate from dev deps
* pytestmark needs to be applied separately for each and every file, this fixes the tests
* use pathlib for resolving relative paths
* Skip discovery doctest on python3.7
The code is just fine, but some reason the mocking behaves differently between 3.7 and 3.8.
The latter seems to accept a discrete object for asyncio.run where the former expects a coroutine..
* Adds a transition param to set_brightness(), turn_on(), and turn_off() that specifies the duration in milliseconds that the dimmer switch will take to transition to the new state.
* Fixes bug where set_brightness(0) was allowed even though the dimmer does not support it. Now brightness values of 0 are coerced to 1 to be consistent with bulbs (which do support brightness values of 0).
