Rather than use ESP32 timers, simply spawn a new task that turn on/off LED using simple delays. By avoiding the use of the ESP32 timer, we are no longer limited by the number of Blinkers possible. Also, Blinker relied on the timer interrupt, which crashed when it tried to call Pixel since Pixel in turn uses interrupts from the RMT. Switching to spawned tasks is much cleaner and does not consume more CPU time since the timer interrupts were driven by CPU anyway.
Blinker class and generic LED class are now in extras.h. Blinkable Interface is also in extras.h.
To Do: Incorporate new Blinker class into HomeSpan code