Merge branch 'bbb-webrtc-sfu' of github.com:prlanzarin/bigbluebutton-1 into test-4661

...button/core/apps/users/UserBroadcastCamStartMsgHdlr.scala

...in/scala/org/bigbluebutton/common2/msgs/WebcamsMsgs.scala

bigbluebutton-client/resources/config.xml.template

bigbluebutton-client/resources/prod/BigBlueButton.html

bigbluebutton-client/resources/prod/lib/kurento-extension.js

bigbluebutton-client/resources/prod/lib/kurento-utils.js

bigbluebutton-client/resources/prod/lib/kurento-utils.min.js

...n-client/resources/prod/lib/reconnecting-websocket.min.js

...g/bigbluebutton/modules/users/services/MessageReceiver.as

bigbluebutton-html5/client/main.html

...tton-html5/imports/api/screenshare/client/bridge/index.js

...on-html5/imports/api/screenshare/client/bridge/kurento.js

...rts/api/screenshare/server/handlers/screenshareStarted.js

...rts/api/screenshare/server/handlers/screenshareStopped.js

...luebutton-html5/imports/api/video/server/eventHandlers.js

...mports/api/video/server/handlers/userSharedHtml5Webcam.js

...orts/api/video/server/handlers/userUnsharedHtml5Webcam.js

bigbluebutton-html5/imports/api/video/server/index.js

bigbluebutton-html5/imports/api/video/server/methods.js

...html5/imports/api/video/server/methods/userShareWebcam.js