Use Google schema files

[Michael Hallock]

Google has released a new repo that is supposed to contain JSON schema / YAML files that describe their entire smart home schema: https://github.com/actions-on-google/smart-home-schema

The scripts that generate DeviceTypes, TraitTypes, and CommandType should move to be generated from this repo instead of attempting to scrape the Google documentation site.

In addition, look into whether the following can be generated automatically from these:

1. googleDevices.json validation / trait validation
2. Trait JSON examples

[Michael Hallock]

Fixed in 2.0.