Starts structuring the documentation library usage into Tutorials, Guides, Explanations and Reference.
Continues migrating new docs from rst to markdown.
Extends the test framework discovery mocks to allow easy writing and testing of code examples.
This should prevent child fixtures from hubs breaking tests due to
missing discovery info. To get these devices in `filter_fixtures`
include protocol string of `SMART.CHILD`.
This is in preparation for tests based on supporting features amongst
other tweaks:
- Consolidates the filtering logic that was split across `filter_model`
and `filter_fixture`
- Allows filtering `dev` fixture by `component`
- Consolidates fixtures missing method warnings into one warning
- Does not raise exceptions from `FakeSmartTransport` for missing
methods (required for KS240)
