OO-2985: scroll to the warning message if someone want to delete its work in the drawing interaction

OO-2969: implement the possibility to choose between several alternative question types during the conversion process

OO-2969: implements process to mark question as "OpenOLAT" question that the editor can open, implements feedback based on conditions, implements unified feedback editor with condition based feedbacks, make the unknown question panel html match the runtime html markup

OO-2328: fix links with a servlet context, show comments in single page export, show a placeholder for videos in PDF, fix sliders javascript errors...

OO-2896: implement a plugin for tinymce to count the number of characters of its content (inclusive HTML markup) and enable it for the info messages editor and the forum

OO-2939 remove unnecessary width and height on movie element, remove legacy responsive css for mediaelement

OO-2871: allow the hotspot interaction to be responsive on small screen, allow the author to resize the background images

OO-2868 improve copy/paste links by wrapping them in an input field for proper selection without trailing whitespace