Added examples/rtp-forwarder

Add new example that demonstrates how to take WebRTC to RTP.
Also provides instructions and pre-canned SDP so you can easily
playback in VLC and ffmpeg.

Resolves #1061

examples/rtp-forwarder/jsfiddle/demo.js

@@ -0,0 +1,38 @@
+/* eslint-env browser */
+
+let pc = new RTCPeerConnection({
+  iceServers: [
+    {
+      urls: 'stun:stun.l.google.com:19302'
+    }
+  ]
+})
+var log = msg => {
+  document.getElementById('logs').innerHTML += msg + '<br>'
+}
+
+navigator.mediaDevices.getUserMedia({ video: true, audio: true })
+  .then(stream => {
+    pc.addStream(document.getElementById('video1').srcObject = stream)
+    pc.createOffer().then(d => pc.setLocalDescription(d)).catch(log)
+  }).catch(log)
+
+pc.oniceconnectionstatechange = e => log(pc.iceConnectionState)
+pc.onicecandidate = event => {
+  if (event.candidate === null) {
+    document.getElementById('localSessionDescription').value = btoa(JSON.stringify(pc.localDescription))
+  }
+}
+
+window.startSession = () => {
+  let sd = document.getElementById('remoteSessionDescription').value
+  if (sd === '') {
+    return alert('Session Description must not be empty')
+  }
+
+  try {
+    pc.setRemoteDescription(new RTCSessionDescription(JSON.parse(atob(sd))))
+  } catch (e) {
+    alert(e)
+  }
+}