Adds an initial version of a logging framework for logging events to an InfluxDB database.

Conflicts:
	src/org/jitsi/videobridge/Videobridge.java
Adds logging for ICE-related events.
Renames the column for conference and channel created/expired events. Minor refactoring.
Logs creation of new Endpoint-s.
Logs the focus JID.
Adds focus-related events to the factory.
Logs display names, if they are provided via COLIBRI.
Adds documentation for logging to influxdb.