Add an endpoint or a script to delete unused map points.

[garg3133]

There is a MapPoints model in the geolocation app, which contains the latitude/longitude information for all the cities where our alumni network is present. But some of these points are outdated (with 0 alumni members) and are still shown on the map.

So, we should have either an endpoint which we can hit or a script which we can run on the server to delete the map points corresponding to which there are no Profile instances that exist.