include paths should not be relative starting with "../

It leads to problems with certain compilers, when Bullet/src is located in a long pathname.
Keep include path starting with "LinearMath/, "BulletCollision/, or "BulletDynamics/

src/BulletCollision/BroadphaseCollision/btAxisSweep3.h

@@ -19,8 +19,8 @@
 #ifndef AXIS_SWEEP_3_H
 #define AXIS_SWEEP_3_H
 
-#include "../../LinearMath/btPoint3.h"
-#include "../../LinearMath/btVector3.h"
+#include "LinearMath/btPoint3.h"
+#include "LinearMath/btVector3.h"
 #include "btOverlappingPairCache.h"
 #include "btBroadphaseProxy.h"
 

src/BulletCollision/BroadphaseCollision/btBroadphaseInterface.h

@@ -21,7 +21,7 @@ subject to the following restrictions:
 struct btDispatcherInfo;
 class btDispatcher;
 struct btBroadphaseProxy;
-#include "../../LinearMath/btVector3.h"
+#include "LinearMath/btVector3.h"
 
 ///BroadphaseInterface for aabb-overlapping object pairs
 class btBroadphaseInterface

src/BulletCollision/BroadphaseCollision/btBroadphaseProxy.h

@@ -16,7 +16,7 @@ subject to the following restrictions:
 #ifndef BROADPHASE_PROXY_H
 #define BROADPHASE_PROXY_H
 
-#include "../../LinearMath/btScalar.h" //for SIMD_FORCE_INLINE
+#include "LinearMath/btScalar.h" //for SIMD_FORCE_INLINE
 
 
 /// btDispatcher uses these types

src/BulletCollision/BroadphaseCollision/btCollisionAlgorithm.h

@@ -16,7 +16,7 @@ subject to the following restrictions:
 #ifndef COLLISION_ALGORITHM_H
 #define COLLISION_ALGORITHM_H
 
-#include "../../LinearMath/btScalar.h"
+#include "LinearMath/btScalar.h"
 
 struct btBroadphaseProxy;
 class btDispatcher;

src/BulletCollision/BroadphaseCollision/btDispatcher.h

@@ -16,7 +16,7 @@ subject to the following restrictions:
 #ifndef _DISPATCHER_H
 #define _DISPATCHER_H
 
-#include "../../LinearMath/btScalar.h"
+#include "LinearMath/btScalar.h"
 
 class btCollisionAlgorithm;
 struct btBroadphaseProxy;

src/BulletCollision/BroadphaseCollision/btOverlappingPairCache.h

@@ -20,8 +20,8 @@ subject to the following restrictions:
 
 #include "btBroadphaseInterface.h"
 #include "btBroadphaseProxy.h"
-#include "../../LinearMath/btPoint3.h"
-#include "../../LinearMath/btAlignedObjectArray.h"
+#include "LinearMath/btPoint3.h"
+#include "LinearMath/btAlignedObjectArray.h"
 
 
 struct	btOverlapCallback