implement a __contains__ method in model/brain object

[andrewheusser]

This is will allow to test for locations in model or brain object e.g.

loc = [34, -20, 50]
loc in bo # returns True if present
loc in mo # returns True if present

[jeremymanning]

Don't we already have something similar with helpers._count_overlapping?

[jeremymanning]

Ah, I see what you mean-- you mean adding support for the in built-in

[andrewheusser]

yup, just syntactic sugar ✨

[jeremymanning]

Sweet