fix(typings): export strava as default + namespace (#101)

Author: ntziolis

index.d.ts

@@ -155,6 +155,6 @@ export interface Strava {
     oauth: OAuthRoutes;
 }
 
-export const strava: Strava;
-
-export default strava;
+declare const strava : Strava;
+export = strava;
+export as namespace strava;