added image to project. Need to adjust size, offset, etc. Need also to investigate CMAKE resource adding

rosbag included. not working and creating error at startup. rest should however still run. safetycheck added again ... switches off and terminates ros when area boundaries are left

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

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