* updated version number to the latest asset version 0.984.4
* updated npm dependencies for security fixes
* updated to ES2016 libraries. Java Script output needs to remain on ES2015 though as Unity 2019.2 builds will fail otherwise
* Bugfix: Make sure all connections are cut on shutdown. In experimental conference mode some connections could remain active after shutdown if some references were kept alive
* Made sure the disconnect method will check the actual id not expect the exact reference of the internal ConnectionId
* added warnings if the user tries to send invalid messages (0 length, null or invalid message id)