Added files for the flying agent GUI, currently compiles in Qt but need significantly testing and development for integrating with ROS

Added a mutex to the RF status label, and adjust the clearing and updating of the bettery status label, seems to be working without too many freezes... will always require more testing

Student gui with icons

See merge request D-FaLL/PandS-System/D-FaLL-System!8

Adjusted battery level image in Student GUI to onlz re-draw when image changes. Tested and seems to be stable.

Adjusted the setup page on the wiki to give more details about flashing new firmware onto the Crazyflie

Moved CF firmware build success pic from the wiki folder to the firmware folder where the readme files that needs this pic is

Adjusted GUI so that all display boxes are checked, and so that the scaling is applied to a CF when it is added (push_back) into the crazyflies_vector

Demo controller back into Master (this branch was used for developing nicer GUI and YAML parameter features for giving demonstrations of the system)

See merge request D-FaLL/PandS-System/D-FaLL-System!7