Adds CORS support

[danielxvu]

First, provision the required dependencies.

git clone -b feature/roll20-improvements [email protected]:Roll20/mediasoup-sandbox.git
cd mediasoup-sandbox/single-page
make
make cert

Next, update config.js to make sure your IP address is being used by the signaling server when relaying IP addresses. (Replace 10.10.0.FIXME with said address when using the following example.)

    // rtp listenIps are the most important thing, below. you'll need
    // to set these appropriately for your network for the demo to
    // run anywhere but on localhost
    webRtcTransport: { listenIps: [{ ip: "10.10.0.FIXME", announcedIp: null }], initialAvailableOutgoingBitrate: 800000 },

You can start running the signaling server now.

make serve

Make a note of the paths to the SSL certificate and key. You will need to modify the Storybook configuration for the grimoire Lerna package in d20app accordingly.