[ocaml] cserial: open serial device with O_NOCTTY to be sure...
[tools] video_synchronizer: added paparazzi icon

closes #786
[ground_segment] different icons for the different applications of paparazzi.

This should prevent the clicking on every icon and parsing through all the windows when we are searching for the messages.
closes #787
[ground_segment] move video_synchronizer to misc
[ardrone2] add download folder to ardrone2 script