system: Start work on system abstraction layer.

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
scripts: move the doxyfile and write doxy make target

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
hal: Add system init functions

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>
system: Hook up memory allocation to system node

Signed-off-by: Bart Kuivenhoven <bemkuivenhoven@gmail.com>