Do not broadcast messages via websocket if there is no client connected

code/espurna/web.ino

@@ -44,8 +44,10 @@ char _last_modified[50];
 // -----------------------------------------------------------------------------
 
 bool wsSend(const char * payload) {
-    DEBUG_MSG("[WEBSOCKET] Broadcasting '%s'\n", payload);
-    ws.textAll(payload);
+    if (ws.count() > 0) {
+        DEBUG_MSG("[WEBSOCKET] Broadcasting '%s'\n", payload);
+        ws.textAll(payload);
+    }
 }
 
 bool wsSend(uint32_t client_id, const char * payload) {