PSA: adapter.js github repository is moving

[Philipp Hancke]

The main adapter.js git repository is moving from its current home at
   https://github.com/webrtc/adapter

to the webrtchacks organisation:
   https://github.com/webrtchacks/adapter

The current license (BSD) will not change. We will make sure the old URLs at
   https://webrtc.github.io/adapter/adapter-latest.js
will continue to work.

There was a small downtime a couple of minutes ago, github caches fooled me but Harald fixed that quickly. Let me know if anything seems still wrong.

If you install the webrtc-adapter package via npm nothing changes. Expect a bit more frequent releases though.

Many thanks to Harald Alvestrand and Christoffer Jansson for handling the maintenance and release chores in the past and the WebRTC organisation for providing the space to grow.

Philipp