Fix "Invalid escape sequence \U" when installing config.h (#230)

Author: rickertm

include/fcl/CMakeLists.txt

@@ -2,10 +2,8 @@ file(GLOB_RECURSE HEADERS            ${CMAKE_CURRENT_SOURCE_DIR}/*.h)
 file(GLOB_RECURSE CONFIGURED_HEADERS ${CMAKE_CURRENT_BINARY_DIR}/*.h)
 set(FCL_HEADERS ${HEADERS} ${CONFIGURED_HEADERS} PARENT_SCOPE)
 
-file(TO_NATIVE_PATH "${CMAKE_CURRENT_SOURCE_DIR}" FCL_CONFIG_IN_DIR)
-file(TO_NATIVE_PATH "${CMAKE_CURRENT_BINARY_DIR}" FCL_CONFIG_OUT_DIR)
-configure_file("${FCL_CONFIG_IN_DIR}/config.h.in" "${FCL_CONFIG_OUT_DIR}/config.h")
-install(FILES "${FCL_CONFIG_OUT_DIR}/config.h" DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/fcl)
+configure_file(${CMAKE_CURRENT_SOURCE_DIR}/config.h.in ${CMAKE_CURRENT_BINARY_DIR}/config.h)
+install(FILES ${CMAKE_CURRENT_BINARY_DIR}/config.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/fcl)
 
 fcl_get_filename_components(
   fcl_header_rel_paths