fixed camera access issues on latest Chrome release + changed version to V1.9845 + updated dependencies

update package.json for usage as npm package. set the version to 1.9844.0 (compatible to 0.9844 of the asset)

* 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)

Upgraded webpack and other depdencies due to npm warning (https://www.npmjs.com/advisories/803) + print error message if the browser autoplay feature blocks the video replay

* Cleanup callapp for easier use
* Support for async init to have video devices available from the first frame
* better work with recent Chrome changes and if loaded via http / file: url’s (mediaDevices null)
* Will fail now during init some WebRTC features aren’t available to avoid cryptic error messages during runtime
* Added GetBufferedAmount

Fixed an error that was triggered if a call was destroyed immediately after a video stream was created but before the video actually started + fixed swapped audio / video toggles in the examples