Add City, Warsaw Opendata (#2306)

README.md

@@ -772,6 +772,7 @@ API | Description | Auth | HTTPS | CORS |
 | [City, Nantes Opendata](https://data.nantesmetropole.fr/pages/home/) | Nantes(FR) City Open Data | `apiKey` | Yes | Unknown |
 | [City, New York Opendata](https://opendata.cityofnewyork.us/) | New York (US) City Open Data | No | Yes | Unknown |
 | [City, Prague Opendata](http://opendata.praha.eu/en) | Prague(CZ) City Open Data | No | No | Unknown |
+| [City, Warsaw Opendata](https://api.um.warszawa.pl/) | Warsaw (PL) City Open Data | `apiKey` | Yes | Unknown |
 | [Code.gov](https://code.gov) | The primary platform for Open Source and code sharing for the U.S. Federal Government | `apiKey` | Yes | Unknown |
 | [Colorado Information Marketplace](https://data.colorado.gov/) | Colorado State Government Open Data | No | Yes | Unknown |
 | [Data USA](https://datausa.io/about/api/) | US Public Data | No | Yes | Unknown |