prevent the Socket.IO server from stopping and cause a redeployment to
fail because of the still running server.

certificate errors with SSL.

(Jetty) environment.
Reduced logging for production environment.

triggered if no Referer-Header was sent.

not valid.

This should perform much better.

Socket.IO about changed active user count.

prevent duplicates if the client uses Socket.IO and still sends the
**/online ping.

LecturerQuestions and Answers to LecturerQuestions.
Renamed events concerning feedback for consistency.

should not be used by the clients.

As a side effect this should smooth the chart animation in arsnova-js.
Added some comments concerning code for legacy HTTP polling support.

server.

server.

UserService instead of a CouchDB request.

UserService.
Added a scheduled method to delete inactive users from
user2sessionLegacy Map.

broadcasting it in reportSessionDataToClient method.

CouchDB and visited sessions.

Socket.IO.

requested.

implementation updates.

interfere with the existing HTTP polling solution.

Some features still need to be ported:
- update session attribute lastOwnerActivity in CouchDB
- add session to visitedSessions in CouchDB
- check if session is locked