Merge pull request #45 from charliejmoore/master

Add data source for historical map GeoJSON

README.md

@@ -112,6 +112,7 @@ GeoJSON utilities that will make your life easier.
 * [strava-geojson](https://github.com/tmcw/strava-geojson): export _all_ strava data to geojson, in node & [on the web](http://www.macwright.org/strava-geojson/)
 * [gimme OSM](http://ustroetz.github.io/gimmeOSM/): Fetch geojson file by openstreetmap id
 * [country-levels](https://github.com/hyperknot/country-levels-export) Full planet GeoJSON extracts, based on ISO and FIPS codes.
+* [historical-basemaps](https://github.com/aourednik/historical-basemaps): Collection of georeferenced boundaries of world countries and cultural regions for use in mapping historical data on the world scale.
 
 ### serialization