Move geospatial backend to MASDAP

Currently all geospatial data resides on [gis-malawi.com](https://gis-malawi.com). 

- [ ] All data should be moved to [MASDAP](http://www.masdap.mw/). 
- [X] GeoServer and Postgres can then be deinstalled on `gis-malawi.com` => Update 30 September 2020: not planned any more (policy by COOPI)