Add Callejero Spain API to Geocoding

README.md

@@ -929,6 +929,7 @@ API | Description | Auth | HTTPS | CORS |
 | [BigDataCloud](https://www.bigdatacloud.com/ip-geolocation-apis) | Provides fast and accurate IP geolocation APIs along with security checks and confidence area | `apiKey` | Yes | Unknown |
 | [Bing Maps](https://www.microsoft.com/maps/) | Create/customize digital maps based on Bing Maps data | `apiKey` | Yes | Unknown |
 | [bng2latlong](https://www.getthedata.com/bng2latlong) | Convert British OSGB36 easting and northing (British National Grid) to WGS84 latitude and longitude | No | Yes | Yes |
+| [Callejero Spain](https://callejero-api.es) | All the information from Callejero (INE Electoral Census) | `apiKey` | Yes | Unknown |
 | [Cartes.io](https://github.com/M-Media-Group/Cartes.io/wiki/API) | Create maps and markers for anything | No | Yes | Unknown |
 | [Cep.la](http://cep.la/) | Brazil RESTful API to find information about streets, zip codes, neighborhoods, cities and states | No | No | Unknown |
 | [CitySDK](http://www.citysdk.eu/citysdk-toolkit/) | Open APIs for select European cities | No | Yes | Unknown |