OO-622,CL-225: remove username from GUI in place where is not really needed and students can see it. Mark others place with //TODO username where it need more works and/or the username is only visible by author/coach/admin... Additional fix the setup sql for MySQL (index too long).

OO-449: show "do not disturb" status in the homepage, list of course members, list of groups members

OO-450 merge link formatter from IM to already existing formatter code, add emoticons formatter for most used emoticons

OO-450 improve chat layout, imitating skype as best practice example. add link to user visiting card. change small portait image size to 30x30 to match icons available in default theme

OO-449: implements notifications for private message, download of log in course and group, archive of log by course deletion...

OO-449: refactor user session to work with identity key, make it pop, implements one to one chat, group chat, course chat, remove connect user list, refactor UserRequest to make it an interface

OO-449: first part of the implementation: remove smack libraries, refactor controller and unify them, implements messaging across the OpenOLAT event bus, implements administration part to enable chat...