Initial compatability data

This includes data scraped by the webplatform project, with some data
removed:
- Browser names have been standardized
- Versions representing specific builds have been removed
- Versions that appear invalid have been removed
- Features are the top-level feature hierarchy.  Any 'row' level
  Features have been removed.
- Supports have been removed.

It also include Specification and Maturity data from the MDN KumaScripts
Spec2 and SpecName.