Integration with git

[cpina]

schema-collaboration keeps the JSON in the database with the intention that the data manager can export this and save it somewhere (in the datapackage, git, etc.).

schema-collaboration could integrate with git: collaborators that prefer to use git + a JSON editor could just use it and collaborators that prefer data package creator would be able to use without problems.

This would also help solving the keeping versions of data schemas: #13

(this was requested/commented by someone in the Frictionless data January 2021 community call. Sorry that I don't remember your name)