Added custom function to send statustext on switch_high

Signed-off-by: Simon Egli <simon.egli@tik.ee.ethz.ch>
Merge branch 'master-Swarmix' into send_statustext_aux
Special function for David from ELTE

When triggering the camera the Quad will also send a special statustext
"AUX_BEEP" to trigger bepping of the attached Overo/Embedded PC.

Signed-off-by: Simon Egli <simon.egli@tik.ee.ethz.ch>
Special parsing of incomming USB-statustext messages.
To trigger the camera (release box).

Signed-off-by: Simon Egli <simon.egli@tik.ee.ethz.ch>
Merge branch 'david_special_dual_function_camera_trigger' into DEMO_TRIGGER_CAMERA
Correcting programming mistake

Signed-off-by: Simon Egli <simon.egli@tik.ee.ethz.ch>
Merge branch 'send_statustext_aux' into master-Swarmix
Merge branch 'DEMO_TRIGGER_CAMERA' into master-Swarmix