Catch config::error exception which could be thrown by parser.

I'm not sure if this is necessary as it is not reported, but
worst case is that not doing this could cause malformed
scenario files in the editor folder to crash wesnoth while
browsing in mp_create.

src/multiplayer_create_engine.cpp

@@ -824,7 +824,13 @@ void create_engine::init_all_levels()
 		for(size_t i = 0; i < user_scenario_names_.size(); i++)
 		{
 			config data;
-			read(data, *(preprocess_file(get_user_data_dir() + "/editor/scenarios/" + user_scenario_names_[i])));
+			try {
+				read(data, *(preprocess_file(get_user_data_dir() + "/editor/scenarios/" + user_scenario_names_[i])));
+			} catch (config::error & e) {
+				ERR_CF << "Caught a config error while parsing user made (editor) scenarios:\n" << e.message << std::endl;
+				ERR_CF << "Skipping file: " << (get_user_data_dir() + "/editor/scenarios/" + user_scenario_names_[i]) << std::endl;
+				continue;
+			}
 
 			scenario_ptr new_scenario(new scenario(data));
 			if (new_scenario->id().empty()) continue;