Feature Request: add examples and references for Mongo query syntax to Docs

[rkingsbury]

The documentation currently makes reference to PyMongo query syntax without providing any links or examples. We should add a tutorial page to the docs describing the basics of pymongo queries, with a link to more advanced tutorials such as this page.

I hereby assign this to myself, unless someone else beats me to it :)

[Andrew-S-Rosen]

Commenting to say that I agree this is an important aspect missing from the docs. I do not hereby assign myself to it, however, at least for the time being. 😉

[rkingsbury]

As a baby step that you can use in the mean time, I've created a tutorial notebook for pyEQL (which uses a maggma Store) which contains instructions for using query, distinct, and count. I will probably draw heavily from this to add something to the maggma docs.

https://pyeql.readthedocs.io/en/latest/examples/pyeql_tutorial_database.html#How-to-Search-the-Database