Prevent stack overflow when flashing px4io

Large local variable causing stack overflow when attempting to flash
IO!!!
Read the full buffer

sizeof wont work here since file_buf is now a pointer
Merge pull request #1158 from jean-m-cyr/master

Prevent stack overflow when flashing px4io
Fixed the submodule check logic
mavlink: use all outputs in HIL mode
Merge pull request #1162 from PX4/hil_outs_fix

mavlink: use all outputs in HIL mode
Hotfix: Close fd before reusing it again
Merge branch 'master' of github.com:PX4/Firmware
Better Doxygen for topics, no code changes
GPS driver: Print velocity as part of status command
Merge pull request #1169 from PX4/comment-fixes

Better Doxygen for topics, no code changes
Add a check command and fix error reporting
Hotfix: fix typo
Commander: More hotfixes to prearm check routine
Make commander error message more verbose
Stop warning users just because they shake a bit, be more strict to catch sensor failures or calibration errors in time
Merge pull request #1168 from PX4/gps_printing

GPS driver: Print velocity as part of status command
Create a mixer for the Wing Wing.
The wing wing is too small to have flaps, gimbals, etc.
Renamed mixer file.