Fix (razzle-dev-utils): make webpackHotDevClient work w/ webpack-dev-server v4
Fix (razzle-dev-utils): make webpackHotDevClient work w/ webpack-dev-server v4

Fix (#1704) webpackHotDevClient for v4 by importing and using the two replacement APIs for the v3 `createSocketUrl` (i.e. `parseURL` and `createSocketURL`).

Also, because the created socket url for v4 is of the form `ws://<hostname/ws` create the connection using the browser native `WebSocket` API instead of `SocksJS`

jaredpalmer/razzle,jaredpalmer/razzle