Changes to the header includes for all STM32 peripherals
to remove variations, redundancies, add missing, fix errors. All c files
refer only to the dispatch style headers in /include/stm32. Those headers
#include memorymap.h and cm3/common.h. All references to
these are removed from the family specific headers. Ethernet untouched as
it appears incomplete.

Added dummy spi.c for F0/F3. Fix some doxygen anomalies.
add dac support to stm32 f0