gpio_led app added
Use work_queue instead of thread
Merge branch 'master' into gpio_led
Merge branch 'master' into gpio_led
Added GPIO_EXT1/GPIO_EXT2 selection.
Code style fixed
mkblctrl cleanup
mkblctrl cleanup & tested
comments cleaned
Merge pull request #286 from NosDE/master

mkblctrl cleaned up and flown with px4 stack and arducopter
Merge pull request #267 from DrTon/gpio_led

gpio_led app added: drive LEDs by GPIO_EXT1 pin of PX4FMU
Hotfix: Generate map files for modules as well for more in-depth memory-use debugging.
Hotfix: Made HMC driver more verbose to prevent false alarm
Hotfix: Completely silencing HMC5883 probing to not confuse users