Fix challenge model and api bugs

Author: dcastrowa

maproulette/api/challenge.py

@@ -302,7 +302,7 @@ def update_challenge(self, challenge_id, data):
         if self.is_challenge_model(data):
             data = ChallengeModel.to_dict(data)
         response = self.put(
-            endpoint=f"/challenge{challenge_id}",
+            endpoint=f"/challenge/{challenge_id}",
             body=data)
         return response
 

maproulette/models/challenge.py

@@ -360,8 +360,8 @@ def to_dict(self):
             "osmIdProperty": self._osm_id_property,
             "cooperativeType": self._cooperative_type,
             "popularity": self._popularity,
-            "checkInComment": self._check_in_comment,
-            "checkInSource": self._check_in_source,
+            "checkinComment": self._check_in_comment,
+            "checkinSource": self._check_in_source,
             "requiresLocal": self._requires_local,
             "defaultBasemap": self._default_basemap,
             "defautlBasemapId": self._default_basemap_id,