Support Geo-map Field module

Added support for the module. Not sure if it needed to be in a submodule or just in the base. So didn't add any tests yet. But shouldn't be that difficult to add. But first would like a review of a maintainer on whether it needs to be a submodule or not.

Will get this into 3.x with tests

I’ll probably move it into the core module, as it doesn’t introduce new entities or graphql module plugins, and is just a field type/resolver.

Merged in 3.x