I2S: Adapted the interrupt routines to the latest changes of hiperspi.
Extended the hiperspi module to support channels that run in serial interrupt mode, instead of DMA mode.
DMA: made the interrupt handling routine faster by replaceing C with assembler.
Added the SYSMIC module and its ics43434 implementation.
MyAirCoach: LEDs may now be driven inverted.
Added I2S module.
hiperspi: Added more granular functions SetBuffer, Arm and Trigger as well as Abort.
DMA module: Added documentation and fixed some "const" issue.