for kernels 4.8 onwards.
Some very old stuff might break.
Additional fixes for the ISR code and some tweaks here and
there. I've removed the checks for some operations that might
fail when using the gpiomem interface - which is now the default
way of doing things - if your program segfaults, then you
may need to use sudo on it.
and developed the new ISR - Interrupt Service Routine
handler - much easier than the old waitForInterrupt code!
Minor tweaks to the gpio program to recognise the environment variable
WIRINGPI_DEBUG too, and removed the printing of the errors from the
main wiringPi setup routines (and added some new ones!)
