- bugfix: ReadStream did not work with a "usPeriod" parameter > 0xFFFF (the fix uses...

- bugfix: ReadStream did not work with a "usPeriod" parameter > 0xFFFF (the fix uses/adapts the atmel ReadStream code)
- bugfix: overflow interrupts were not handled/signalled correctly from the HAL
- fixed the wiring for DMA, which was not correct when used by more than one client
- polished the HPL and added some comments
- introduced a compile time warning when DMA/TimerA is accessed (will be removed once we decide how these components are arbitrated)