[ardrone2] add rm_dir command
[ardrone2] send filter status from navboard

- it allows to see if the mag is crashed or not
- set a max retry on the reset PIC board hack (which doesn't seems to
  help anyway)
[module] add agl_dist module
[math] fix polyfit init
[airframes] fix quad_navgo actuators for nps
New joystick file for RC trainer
[modules] Added temperature adc module

Added temperature driver for analog sensors (LM35 and 100k NTC)

closes #857
[modules] add airspeed_ms45xx_i2c module

- differential pressure is filtered with a butterworth lowpass
- including (persistent) settings for pressure scale and offset
- add AIRSPEED_MS45XX message

closes #852
[nav] takeoff detection module

set the launch variable to true based on pitch angle