- add more logs to trace messages
 - add FS status check by sending ESL message to FS

 - FreeSWITCH core dumped and akka-fsesl managed to reconnect. However, commands (mute, unmute, record, etc.) to FS are not reaching FS.
   But events (user joined, left, talking) from FS are received by akka-fsesl. Can't determine where the commands are falling off. These
   extra logging hopefully helps us narrow down if this happens again.

   I wasn't able to reproduce the issue when stopping and restarting FS. Akka-fsesl reconnects and command/events are flowing in both
   directions.

   This will help us hunt an issue where a channel gets stuck in a voice conference.

 - fix screenshare redis connection error
 - fix bbb-web create meeting exception when second user joins

fsesl wait for freeswitch; change links by depends_on; remove freeswitch ipv6 config files; enable wss-binding element on freeswitch; fix kurento listen only

 - use webrtc screenshare using FS Verto
 - publish screenshare as rtmp to red5
 - flash clients view screenshare from red5 rtmp

 Fix mute/unmute/talking of user in voice conference