Fixes resolving this when passing function after enabling es6.

Finds correct error when getUserMedia succeed with only one of the audio or video, and the other fails.

Fixes the availableDevices, to reflect the devices for which we succeeded or failed to obtain stream.

Stores render event in connection times to use it for tests.

Moves render time calculations in the library.

On Safari/IE we have to wait until the WebRTC stack is
initialized in case the plugin is being installed for
the first time.