Is your feature request related to a problem? Please describe.

as a developer
when I edit the config.yml
and I make changes incompatible with netlifycms
I want my editor to make me aware of the invalid changes and why they're invalid.

Describe the solution you'd like

Provide a hosted jsonschema over at https://www.schemastore.org/json/

Describe alternatives you've considered

• Spend the rest of my life continually pressing F5 on the netlifycms github page and analysing all possible code changes that might create changes to a valid config. 🤮
• rely on runtime errors 🤮

Additional context