Add C++0x support in CMake

You need to add the flag to CMAKE_CXX_FLAGS:

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")

I use this snippet for GCC, but it is a more complicated way:

if(CMAKE_COMPILER_IS_GNUCXX)
   SET(ENABLE_CXX11 "-std=c++11")

   EXECUTE_PROCESS(COMMAND "${CMAKE_CXX_COMPILER} -dumpversion" OUTPUT_VARIABLE GCC_VERSION)
   if (GCC_VERSION VERSION_LESS 4.7)
      SET(ENABLE_CXX11 "-std=c++0x")
   endif()

   SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${ENABLE_CXX11}")
endif()