compatibility with both ws and sockjs

[snitin315]

Currently, the plugin is using the sockjs-client for devServer which was default in webpack-dev-server@3.

error-overlay-webpack-plugin/src/entries/devserver.mjs

Line 4 in 8aa4edf

import SockJS from 'sockjs-client'

error-overlay-webpack-plugin/src/entries/devserver.mjs

Lines 13 to 19 in 8aa4edf

	const connection = new SockJS(
	`${window.location.protocol}//${
	sockOptions.sockHost || window.location.hostname
	}:${sockOptions.sockPort || window.location.port}${
	sockOptions.sockPath || '/sockjs-node'
	}`,
	)

webpack-dev-server@v4 changed the default to ws, it would be great if the plugin can support both. Otherwise we have errors in console with webSocketServer: 'ws'

[giladgd]

Until my fix PR (#105) is merged you can use this workaround:

npm install --save-dev "github:giladgd/error-overlay-webpack-plugin#wsErrorMessageFix/compiled"

This will install a branch I created with the fix and with compiled files to make it work properly as a node module