multiple upgrades & fixes

upgrade :
_ the whole the movement process : possibility to queue movement =>
possibility to move "further" if wanted
_ add new translation / rotation to better see the guardian (when in
riddle)
_ movement (rotation and translation) : now moves by a fixed step every
iteration (whatever the destination)

fix :
_ fix the "clic and move" problem : only a real clic will move the
camera => possibility to rotate even when originally clicking on the
ground
_ removed MANY unused variables