Add docstrings for Schema methods.
Add docstrings for Schema methods.

ncalexan/datomish,ncalexan/mentat,ncalexan/mentat,ncalexan/mentat,mozilla/mentat,ncalexan/mentat,ncalexan/datomish,mozilla/mentat,mozilla/mentat,ncalexan/mentat,mozilla/mentat,ncalexan/mentat,mozilla/mentat,mozilla/mentat