Create random device UUIDs

• Major fix: Added missing random seed to device UUID generation
• Added default EspSigK debug HTTP server at port 8080
• Added option to call local handler during safeDelay()
• Added overloaded deltaValue() functions to String and const char * value types
• Added setWiFiConnectTimeout() and changed default wifi timeout from 3 seconds to 10 secs
• Fix: Added missing ESP32SSDP library (required for ESP32)
• Fix: Added prefix for internal defined names (settings) to overcome overlapping names
• Fix: Do not block handle() calls if wifi is not available