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
Added limit to heading command
Merge branch 'master' of github.com:PX4/Firmware
Based on comments in:

    http://answers.px4.ethz.ch/question/1337/px4io-receiver-connection-problem/?answer=1346#post-id-1346

increase the longest PPM pulse we recognize out to 550µs.
mkblctrl cleanup
Reinstate mapfile generation.
Hotfix: fix section attribute for the ROMFS, moving it back into .rodata where it belongs.
mkblctrl cleanup & tested
Adjusted example params and extensively commented example
Go only to RC failsafe if throttle was half once - to prevent failsafe when armed on ground
More documentation
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.