Xfinity Gateway device_tracker platform

[cisasteelersfan]

Description:

Xfinity Gateway device_tracker platform. On the login page of the gateway, a list of connected devices with MAC address & hostname is displayed. My Pypi package scrapes this page using BeautifulSoup.

Related issue (if applicable): fixes #

Pull request in home-assistant.io with documentation (if applicable): home-assistant/home-assistant.io#8535

Example entry for configuration.yaml (if applicable):

device_tracker:
  platform: xfinity

Checklist:

• The code change is tested and works locally.
• Local tests pass with tox. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.

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

• Documentation added/updated in home-assistant.io

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

• New dependencies have been added to the REQUIREMENTS variable (example).
• New dependencies are only imported inside functions that use them (example).
• New or updated dependencies have been added to requirements_all.txt by running script/gen_requirements_all.py.
• New files were added to .coveragerc.

If the code does not interact with devices:

• Tests have been added to verify that the new code works.

[rohankapoorcom]

Overall looks good, a few small changes requested.

[rohankapoorcom]

Can be merged when build passes.

[MartinHjelmare]

Nice!