Merge pull request #8516 from jia200x/wiki_dox_convertion

boards/acd52832/doc.txt

boards/acd52832/include/board.h

boards/airfy-beacon/doc.txt

boards/airfy-beacon/include/board.h

boards/arduino-due/doc.txt

boards/arduino-duemilanove/doc.txt

boards/arduino-duemilanove/include/board.h

boards/arduino-mega2560/doc.txt

boards/arduino-mega2560/include/board.h

boards/arduino-mkr1000/doc.txt

boards/arduino-mkr1000/include/board.h

boards/arduino-mkrfox1200/doc.txt

boards/arduino-mkrzero/doc.txt

boards/arduino-mkrzero/include/board.h

boards/arduino-uno/doc.txt

boards/arduino-uno/include/board.h

boards/arduino-zero/doc.txt

boards/arduino-zero/include/board.h

boards/avsextrem/doc.txt

boards/avsextrem/include/board.h