Added HACD library by Khaled Mamou, for improved convex decomposition

See also http://sourceforge.net/projects/hacd/ and http://bulletphysics.org/Bullet/phpBB3/viewtopic.php?f=4&t=6619
Thanks to Sujeong Kim for the integration with the Bullet/Demos/ConvexDecompositionDemo

Extras/HACD/CMakeLists.txt

@@ -0,0 +1,51 @@
+INCLUDE_DIRECTORIES(
+ ${BULLET_PHYSICS_SOURCE_DIR}/Extras/HACD
+)
+
+SET(HACD_SRCS
+	hacdGraph.cpp
+	hacdHACD.cpp
+	hacdICHull.cpp
+	hacdManifoldMesh.cpp
+)
+
+SET(HACD_HDRS
+	hacdCircularList.h
+	hacdGraph.h
+	hacdHACD.h
+	hacdICHull.h
+	hacdManifoldMesh.h
+	hacdVector.h
+	hacdVersion.h
+	hacdCircularList.inl
+	hacdVector.inl	
+)
+
+ADD_LIBRARY(HACD ${HACD_SRCS} ${HACD_HDRS})
+SET_TARGET_PROPERTIES(HACD PROPERTIES VERSION ${BULLET_VERSION})
+SET_TARGET_PROPERTIES(HACD PROPERTIES SOVERSION ${BULLET_VERSION})
+
+#IF (BUILD_SHARED_LIBS)
+#  TARGET_LINK_LIBRARIES(HACD BulletCollision LinearMath)
+#ENDIF (BUILD_SHARED_LIBS)
+
+IF (INSTALL_EXTRA_LIBS)
+	IF (NOT INTERNAL_CREATE_DISTRIBUTABLE_MSVC_PROJECTFILES)
+		#FILES_MATCHING requires CMake 2.6
+		IF (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 2.5)
+			IF (APPLE AND BUILD_SHARED_LIBS AND FRAMEWORK)
+				INSTALL(TARGETS HACD DESTINATION .)
+			ELSE (APPLE AND BUILD_SHARED_LIBS AND FRAMEWORK)
+				INSTALL(TARGETS HACD DESTINATION lib${LIB_SUFFIX})
+				INSTALL(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+DESTINATION ${INCLUDE_INSTALL_DIR} FILES_MATCHING PATTERN "*.h"  PATTERN
+".svn" EXCLUDE PATTERN "CMakeFiles" EXCLUDE)
+			ENDIF (APPLE AND BUILD_SHARED_LIBS AND FRAMEWORK)
+		ENDIF (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 2.5)
+
+		IF (APPLE AND BUILD_SHARED_LIBS AND FRAMEWORK)
+			SET_TARGET_PROPERTIES(HACD PROPERTIES FRAMEWORK true)
+			SET_TARGET_PROPERTIES(HACD PROPERTIES PUBLIC_HEADER "${HACD_HDRS}")
+		ENDIF (APPLE AND BUILD_SHARED_LIBS AND FRAMEWORK)
+	ENDIF (NOT INTERNAL_CREATE_DISTRIBUTABLE_MSVC_PROJECTFILES)
+ENDIF (INSTALL_EXTRA_LIBS)