add package for generalised functions, packages
create generalised functions for data storage

functions from boat_imu generalised
create mission planner package
add path planner package
add setup.py so py function in src can be used

the setup.py can't (!) be used for python directly
it is called by ros/catkin (?)
in the CMakeList
add src subfolder for python libraries
add pid control package
add message_runtime to CMakeLists
add package for estimating current heading
add package for publishing wind direction data
add package for publishing gps position data
add setup.py for catkin
add packages for controling sail and rudder servos
add general functions packet dependency