Add option to newsfeed for logging errors

- 'logFeedWarnings' added to newsfeed config, defaulted to false
- Only log parse feed errors when logFeedWarnings is true
- Updated README and CHANGELOG
- Fixes #1329

modules/default/newsfeed/newsfeed.js

@@ -37,7 +37,8 @@ Module.register("newsfeed",{
 		startTags: [],
 		endTags: [],
 		prohibitedWords: [],
-		scrollLength: 500
+		scrollLength: 500,
+		logFeedWarnings: false
 	},
 
 	// Define required scripts.