support multiple actuator control groups

several first changes to INAV optical flow estimation

The available version of cmake for Ubuntu 12.04 is too old.
The PPA listed does not currently work so the official
cmake webisite is a more reliable source to get cmake.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

Added switching from attitude control generated rate setpoints to manual rate setpoints when in rattitude mode

Added commander support for rattitude mode.  Still need to incorporate attitude/rate switching in multicopter control

Ignore .DS_Store in the ROMFS pruner.

Sitl startup script

MacOS was having isues with DHCP for NFS shared folder

Signed-off-by: Mark Charlebois <charlebm@gmail.com>