Move EventStream to external module

server/eventStreamSource.js

@@ -0,0 +1,9 @@
+import { EventEmitter } from 'events';
+
+const Stream = new EventEmitter;
+
+export default {
+	emit : function(event) {return Stream.emit(event, ...([...arguments].slice(1)));},    // Arguments doesn't work for arrow functions
+	on   : (event, listener)=>{return Stream.on(event, listener);},
+	off  : (event, listener)=>{return Stream.off(event, listener);}
+};