[openaddresses] Adding DC (not a state, but in after the original 13 colonies)

resources/parser/data_sets/openaddresses.yaml

@@ -192,6 +192,12 @@ countries:
                     - filename: town_of_groton.csv
                       add_osm_boundaries: true
 
+            dc:
+                add:
+                    state: DC
+                files:
+                    - filename: statewide.csv
+
             de:
                 add:
                     state: DE