Get docs dynamically

[lambdamusic]

We want to have a way to always have up-to-date schema definition.

This can be achieved via the describe schema command and version number checking:

• store docs locally
  • in schema.dict.py in local folder
  • either in folder name or elsewhere store also the version number
• at runtime, check if current version matches the cached grammar version
  • if not, call refresh_schema() before anything else
  • then start dimcli