[CMake] install headers

include/dynamic-graph/python/CMakeLists.txt

@@ -11,4 +11,7 @@ SET(${PROJECT_NAME}_HEADERS
   signal-wrapper.hh
 )
 
+INSTALL(FILES ${${PROJECT_NAME}_HEADERS} DESTINATION include/${CUSTOM_HEADER_DIR})
+
 CONFIG_FILES(link-to-python.hh)
+INSTALL(FILES ${CMAKE_CURRENT_BINARY_DIR}/link-to-python.hh DESTINATION include/${CUSTOM_HEADER_DIR})