V3

Yeah I think our GeoFire clients should operate under the assumption that the schema of the GeoFire node is correct. If it is not, unexpected things will happen anyways. If we do run into a bad schema state, we should throw an error explaining as much. For example throw an error with the message `"Unexpected GeoFire location object encountered: " + JSON.stringify(geoFireObj)`. Does that sound reasonable to you?