Bug 1779446, Player kart rescue does not work, fixed.

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/trunk/supertuxkart@1217 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/moveable.cpp

@@ -151,7 +151,11 @@ void Moveable::update (float dt)
     }   // if m_history_position
     const float HAT = m_curr_pos.xyz[2]-HOT;
 
+#ifdef BULLET
+    m_on_ground = ( HAT <= 1.5 );
+#else
     m_on_ground = ( HAT <= 0.01 );
+#endif
 
     doCollisionAnalysis(dt, HOT);