Added reasons to assertions

src/dawn/prefab/Prefab.hpp

@@ -29,7 +29,7 @@ namespace Dawn {
        * @return The instance of the created prefab.
        */
       static O * create(J *context) {
-        assertNotNull(context);
+        assertNotNull(context, "Prefab::create: Context cannot be null");
         return P::prefabCreate(context);
       }
   };