remove extra step for parsing facebook response as was returning nil

Author: mlennie

lib/omnicontacts/authorization/oauth2.rb

@@ -56,9 +56,6 @@ def token_req_params code
       end
 
       def access_token_from_response response
-        if auth_host == "graph.facebook.com"
-          response = query_string_to_map(response).to_json
-        end
         json = JSON.parse(response)
         raise json["error"] if json["error"]
         [json["access_token"], json["token_type"], json["refresh_token"]]