Add auto-scrolling for containers

This is basically copy/paste work from the auto scrolling for text boxes. It adds the same feature for containers which would make my home screen in Xperience1080 a little bit easier because I could get rid of all the AlarmClocks and just add

<autosrcoll time="4000">Container(20).HasFocus(id) + !Control.HasFocus(list_id)</autosrcoll>

to all the widgets.

Thanks
`Black