Fix Issue #16364 dev-doc: Documentation empty

[tmonck]

Description:

Add readthedoc.yml file to specify the version of python to run during documentation building.

Read the docs was building documentation in Python 3.5.2 which was causing:
WARNING: autodoc: failed to import module 'homeassistant.bootstrap'; the following exception was raised:
cannot import name 'Coroutine'

Read the docs allows you to specify the required version of python by using a yaml file. https://docs.readthedocs.io/en/latest/yaml-config.html

Related issue (if applicable): fixes #16364

Pull request in home-assistant.io with documentation (if applicable): home-assistant/home-assistant.io#<home-assistant.io PR number goes here>

Example entry for configuration.yaml (if applicable):

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass

If user exposed functionality or configuration variables are added/changed:

If the code communicates with devices, web services, or third-party tools:

If the code does not interact with devices:.

[homeassistant]

Hi @tmonck,

It seems you haven't yet signed a CLA. Please do so here.

Once you do that we will be able to review and accept this pull request.

Thanks!

[tmonck]

Not sure why the pylint portion of travis-ci build failed. Any guidance on fixing that would be appreciated.

[tmonck]

https://home-assistant-doc-test.readthedocs.io/en/latest/api/bootstrap.html is it working in my personal readthedocs. I only used this for testing and plan on removing once this PR merges.

[fabaff]

CI should pass now.

[tmonck]

Thanks @fabaff.

[balloob]

oooh thanks !