send presenter group to late joiner

...ebutton/core/apps/users/GetPresenterGroupReqMsgHdlr.scala

...in/scala/org/bigbluebutton/core/apps/users/UsersApp.scala

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

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

.../main/scala/org/bigbluebutton/common2/msgs/UsersMgs.scala

...ent/src/org/bigbluebutton/main/model/users/UserService.as

...ton/main/model/users/events/RequestPresenterGroupEvent.as

.../bigbluebutton/modules/present/managers/PresentManager.as

...g/bigbluebutton/modules/present/maps/PresentEventMap.mxml

...bluebutton/modules/present/ui/views/FileUploadWindow.mxml

...g/bigbluebutton/modules/users/maps/UsersMainEventMap.mxml

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

...org/bigbluebutton/modules/users/services/MessageSender.as