Currently, the default behaviour on linux boards tries to
write LED gpios with fixed values among them. There is no way
to declare that there are no LED GPIOs.
This commit moves the declaration of the LED Gpios in AP_HAL_Boards.h
and makes AP_Notify do nothing if no LED gpio was declared
This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.