Querying for geospatial data from flatgeobuffs in the cloud.

[stuartlynn]

Some example code here: https://github.com/stuartlynn/pop_getter_getter/blob/main/src/main.rs

Take the definition of a boundary file + any relevant search / filter parameters (as defined in #3) and return a vector of geometry objects with IDs.

[stuartlynn]

This is mostly accomplished by #14. We might want to tweak the output of that function to be only (id,geometry) tuples but we can revisit that as we start using the function