LED_BUILTIN is NOT defined for all ESP32 boards - some do not have a built-in LED! Instead, Status LED now defaults to Pin 13, as opposed to LED_BUILTIN. Also, added a new method, homeSpan.getStatusPin(), to return the pin number used for the Status LED, whether or not it remains the default (13) or is changed by user with homeSpan.setStatusPin(pin). This method is now used in the DEV_Identify.h file for each example, instead of using LED_BUILTIN (which otherwise won't compile for boards without a built-in LED)
Modified SpanCharacteristic::sprintfAttributes to streamline logic and add special handling for the ProgrammableSwitchEvent Characteristic as required by HAP: the value returned for the database or any read request must be set to null (i.e. "value":null). The only time the real value should be returned is when the device sends a EV/Notify message (when the button is pressed). Verified that the example works as expected!
TO DO: Add functionality to allow for Service Namespace and Index label so that you can have multiple programmable pushbuttons in one service - this requires logic for HAP LINKED SERVICE functionality.
Gregg