Add Query.get_meta()

[chrisimcevoy]

Adds get_meta() to Query

closes #249

[chrisimcevoy]

I'll take a look at the lint error.

[chrisimcevoy]

 + mypy tests typings
typings/django/db/models/sql/query.pyi:95:27: error: Missing type parameters for generic type "Options"  [type-arg]
Found 1 error in 1 file (checked 693 source files)

Interesting. Same return type as upstream.

The django-types Options uses the generic type parameter (_M) several times (source). I notice that django-stubs still has the generic type parameter on its Options, but it appears to be otherwise unused. 🤔