PLGTG-17 Add other kind of overlays instead of image
Also allow global positioning if no element is specified (in this case, it's left/top 0/0)
Could plug width and height as well
PLGTG-18 Allo to use return-line HTML with adding simple carriage return
PLGTG-19 Use of trigger for running the actions (instead of action keyword)
PLGTG-20 Allow to add wiki hyperlinks