Move the following util classes into src folder:
- StatsBar
- JsSelectToInput
- MessageWebImporter
- StatsTable
- TuxMessageTable
- HTMLJsSelectToInputField
See: https://www.mediawiki.org/wiki/Extension:Translate/Namespaces to identify where to move them.
Also add strict types and remove unnecessary comments as mentioned here: https://www.mediawiki.org/wiki/Help:Extension:Translate/Developer_guide