examples/tests: blacklisted arduino-due
cpu: Initial import of cortexm_common files

- fixes to cortexm-common
- Added ARM CMSIS headers to cortexm_common
- thread_exit fixes to cortexm-common
- cortexm-common adjusted documentation

- cortexm_common added eINT dINT defines for now
cpu: Initial import of SAM3X8E

- fixed spelling in uart driver
- marked cortexm-common a phony target
- fixed Makefiles
- added reboot interface implementation
- fixed documentation

- added UART0_BUFSIZE define

- added license header

- fixed documentation issues
board: Initial import of arduino-due

- 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
Merge pull request #1107 from haukepetersen/sam3x8e

board: Initial import of the arduino-due