Finished with controller, therefore we merge

Merge branch 'controller_update' of https://gitlab.ethz.ch/D-FaLL/D-FaLL-System into controller_update

This has to be done

changes to CMakeList, Crazyflie.launch and CustomControllerService -- all concerning the CustomControllerService

Merge branch 'controller_update' of https://gitlab.ethz.ch/D-FaLL/D-FaLL-System into controller_update

added student controller framework called CustomControllerService---hopefully now it actually pushes the file..

changed the function convertIntoBodyFrame(request, est, state, yaw_measured) such that it uses the measured yaw without considering the setpoint - eliminates the drifting problem but is probably still wrong regarding the controlling logic. Added an rqt-plot to the launch file.

supposedly fixed problem caused when multiple Cf-Objects are selected in Vicon. Plus some cosmetic changes

implemented Kalman filter as state estimator, but position is converging very slowly and causes oscillations in x, y and z direction

safecontroller works fine. still an issue with outYaw cause it overshoots - check comment in safecontroller code. safetycheck for localArea implemented and adjusted - switchoff if out of bounds.

CMakeLists.txt for GUI separated from general file. Now we have two CMakeLists.txt, one for general project, and one for GUI

Added comments to CMakeLists.txt. Thinking now on better solution, maybe having my own CMakeLists.txt inside GUI folder and calling it from this CMakeLists.txt

Merge branch 'controller_update' of https://gitlab.ethz.ch/D-FaLL/D-FaLL-System into controller_update

Merge branch 'controller_update' of https://gitlab.ethz.ch/D-FaLL/D-FaLL-System into controller_update