Fix for disconnects on ESP8266 with static JSON buffer

wled00/wled.cpp

@@ -688,7 +688,7 @@ void WLED::handleConnection()
   // reconnect WiFi to clear stale allocations if heap gets too low
   if (now - heapTime > 5000) {
     uint32_t heap = ESP.getFreeHeap();
-    if (heap < JSON_BUFFER_SIZE+512 && lastHeap < JSON_BUFFER_SIZE+512) {
+    if (heap < MIN_HEAP_SIZE && lastHeap < MIN_HEAP_SIZE) {
       DEBUG_PRINT(F("Heap too low! "));
       DEBUG_PRINTLN(heap);
       forceReconnect = true;