Merge branch '2.3-per-user-wb' into develop

...rc/main/scala/org/bigbluebutton/SystemConfiguration.scala

...n/scala/org/bigbluebutton/core/apps/WhiteboardModel.scala

...tton/core/apps/whiteboard/ClearWhiteboardPubMsgHdlr.scala

.../apps/whiteboard/GetWhiteboardAnnotationsReqMsgHdlr.scala

...re/apps/whiteboard/ModifyWhiteboardAccessPubMsgHdlr.scala

...n/core/apps/whiteboard/SendCursorPositionPubMsgHdlr.scala

.../apps/whiteboard/SendWhiteboardAnnotationPubMsgHdlr.scala

...utton/core/apps/whiteboard/UndoWhiteboardPubMsgHdlr.scala

.../bigbluebutton/core/apps/whiteboard/WhiteboardApp2x.scala

akka-bbb-apps/src/universal/conf/application.conf

...scala/org/bigbluebutton/common2/msgs/WhiteboardMsgs.scala

.../api/annotations/server/handlers/whiteboardAnnotations.js

...oard-multi-user/server/handlers/modifyWhiteboardAccess.js

...html5/imports/api/whiteboard-multi-user/server/helpers.js

...html5/imports/api/whiteboard-multi-user/server/methods.js

...i/whiteboard-multi-user/server/methods/addGlobalAccess.js

...iteboard-multi-user/server/methods/addIndividualAccess.js

...hiteboard-multi-user/server/methods/removeGlobalAccess.js

...board-multi-user/server/methods/removeIndividualAccess.js

...ard-multi-user/server/modifiers/modifyWhiteboardAccess.js