Add a basic map with the districts of NRW, search for name on click

This is an inital approach to spatial access to the NWBib data.
It's related to #3, but it doesn't use the spatial classification.

Data from [1], converted with topojson for [2], see docs at [3].

topojson --id-property RS -p name=GEN -p name -o topo.json geo.json

[1] http://opendatalab.de/projects/geojson-utilities
[2] http://datamaps.github.io
[3] http://datamaps.markmarkoh.com/using-custom-map-data-w-datamaps