Allow the client to be used in a nodejs instance

https://github.com/geckosio/geckos.io/blob/0101a7a70a2fae8603ca1c8ea599d3214ab9e0d8/packages/client/src/wrtc/peerConnection.ts#L4

Perhaps, if window does not exist import RTCPeerConnection from node-webrtc?

[gutnar]

I managed to use the client in NodeJS by providing some global variables from wrtc and node-fetch packages.

// Polyfills
import wrtc from "wrtc";
import fetch from "node-fetch";

global.RTCPeerConnection = wrtc.RTCPeerConnection;
global.RTCSessionDescription = wrtc.RTCSessionDescription;
// @ts-ignore
global.fetch = fetch;

// Client can now be used
import geckos from "@geckos.io/client";

[emansom]

It would add two extra (rather large) dependencies to the package.

Which a tree shake algorithm, which most bundlers implement, would filter out.