Additional device for Espruino to support 8 pins in parallel (for discussion)

Last not least, flickering is gone.
Surrounded jsvIterateCallback with rtos commands to switch taskhandling off

vTaskSuspendAll();
  jsvIterateCallback(data, allFast ? jswrap_io_shiftOutCallbackFast : jswrap_io_shiftOutCallback, &d);
xTaskResumeAll();

Actual status, compared to direct_io branch is:

• switched fast io off (return false in jshGetPinAddress)
  
• switched task handling off during jsvIterateCallback
  
• moved en.set() and en.reset() from js(g.scan) to be set in arr
  
  

Latest next week, I'll send a request with all changes to direct_io branch.
Open questions:

• how do we call task relevant RTOS function ? We could use #ifdef ESP32 or #ifdef RTOS. I would prefer the 2nd one.
  
• do we need jshIsPinValid(d->pins[n]) in jswrap_io_shiftOutCallback ? Isn't this already done in jswrap_io_shiftOut ?