[settings] improve settings in pprzcenter

- check box for faster enable/disable
- loading from modules
[settings] add a few more settings in modules
[settings] variable size modules settings area
[settings] add settings directly inside modules files
[settings] allow several groups of settings in modules
[settings] move settings to module files and remove old files
[settings] fix example conf
fix conf_example
remove another unneeded settings file
[udp] change function name to avoid collision with video lib
[fixedwing] nav function to downlink WP after computation
[nav] Set Alt and Pos here
[intermcu] intermcu over CAN link from lisa to lisa
[intermcu_can] main_fbw calling
[link_mcu_can] Call from main
[intermcu] common link_mcu.h header
add ivy2nmea to gitignore
[i2c] also check I2C3
[gcs] select an aircraft directly with a click on the map
[intermcu] style fix