Permission handling is the same as with removed Authorized annotation

joinSession method since HTTP session is out of scope

Renamed TEACHER to SPEAKER to adapt roles to ARSnova client, and
also added some convenience methods for role handling.

This patch uses an in memory storage of logged in users. Every time
users send a (online) heartbeat the last known active timestamp of all
users will be checked and inactive users will be removed from active
user list.

not valid.

CouchDB and visited sessions.

requested.

If the current session is linked to a course and there are other sessions
for this course, add a number to the name and short name of the session,
indicating which session is ment since all sessions will have the same
name and short name.

This fixes Socket.io not broadcasting and accepting feedback data.

API changes:
- /session/visitedsessions => /session/?filter=visited
- /session/mysessions => /session/?filter=owned
Added changed routes to LegacyController.

The method now returns users visited sessions and all sessions connected to
a course the user is enlisted - if connector is activated.

If connector is enabled, user will see in addition to his visited sessions
all sessions linked to his courses.