Remove kart.hpp, it has been compiling fine (add back if compiler dependant).

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@5382 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/tracks/check_structure.cpp

@@ -17,7 +17,6 @@
 //  along with this program; if not, write to the Free Software
 //  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
-#include "karts/kart.hpp"
 #include "modes/world.hpp"
 #include "race/race_manager.hpp"
 #include "tracks/check_manager.hpp"