Merge pull request #4358 from pedrobmarin/shared-notes-changes

.../scala/org/bigbluebutton/core/apps/SharedNotesModel.scala

...ton/core/apps/sharednotes/ClearSharedNotePubMsgHdlr.scala

...igbluebutton/core/apps/sharednotes/SharedNotesApp2x.scala

...on/core/apps/sharednotes/UpdateSharedNoteReqMsgHdlr.scala

...ton/core/pubsub/senders/ReceivedJsonMsgHandlerActor.scala

...n/scala/org/bigbluebutton/core/running/MeetingActor.scala

...cala/org/bigbluebutton/common2/msgs/SharedNotesMsgs.scala

...on-client/src/org/bigbluebutton/core/model/SharedNotes.as

...bluebutton/modules/sharednotes/events/SharedNotesEvent.as

...button/modules/sharednotes/managers/SharedNotesManager.as

...ebutton/modules/sharednotes/maps/SharedNotesEventMap.mxml

...gbluebutton/modules/sharednotes/services/MessageSender.as

...uebutton/modules/sharednotes/views/SharedNotesWindow.mxml

...arednotes/views/components/SharedNotesRichTextEditor.mxml