Rework backend add MQTT and WebSocket support

* Update back end to add MQTT and WebSocket support
* Update demo project to demonstrate MQTT and WebSockets
* Update documentation to describe newly added and modified functionallity
* Introduce separate MQTT pub/sub, HTTP get/post and WebSocket rx/tx classes
* Significant reanaming - more accurate class names
* Use PROGMEM_WWW as default
* Update README documenting PROGMEM_WWW as default
* Update README with API changes

interface/src/authentication/Authentication.ts

@@ -61,3 +61,13 @@ export function redirectingAuthorizedFetch(url: RequestInfo, params?: RequestIni
     });
   });
 }
+
+export function addAccessTokenParameter(url: string) {
+  const accessToken = localStorage.getItem(ACCESS_TOKEN);
+  if (!accessToken) {
+    return url;
+  }
+  const parsedUrl = new URL(url);
+  parsedUrl.searchParams.set(ACCESS_TOKEN, accessToken);
+  return parsedUrl.toString();
+}