This PR converts tabs to white spaces.
The statement I used for the conversion:
```find . -name "*.[ch]" -exec zsh -c 'expand -t 4 "$0" > /tmp/e && mv /tmp/e "$0"' {} \;```
Afterwards, I had a quick overview of the converted files to prevent odd indentation.
- switched to flashing using the programming port
- fixed Makefile.include
- fixes some documentation
- removed newlib nano.specs
- added OSX flashing support
- fixed flasher and port for OSX
- fixed port on OSX
- fixed bossac linux tool
- added license header