removed enable_cxx11_support.cmake, as we must not use it any more

cmake/enable_cxx11_support.cmake

-#######################################################################################################################
-# enable_cxx11_support.cmake
-#
-# NOTE: Do not use this routine! Use enable_latest_css_support.cmake instead, even if you only need C++11, as the
-#       compiler always uses the strictest ("oldest") specified standard if mulitple flags are given. This will create
-#       problems when combining multiple projects (libraries...) requiring different C++ standards.
-#
-# Enable C++-11 support by selecting the appropriate compiler flag. The flag will be appended to all of the following
-# cmake variables:
-# - CMAKE_CXX_FLAGS
-# - ${PROJECT_NAME}_CXX_FLAGS
-# - ${PROJECT_NAME}_CMAKE_CXX_FLAGS
-#
-#######################################################################################################################
-
-#######################################################################################################################
-#
-# IMPORTANT NOTE:
-#
-# DO NOT MODIFY THIS FILE inside a project. Instead update the project-template repository and pull the change from
-# there. Make sure to keep the file generic, since it will be used by other projects, too.
-#
-# If you have modified this file inside a project despite this warning, make sure to cherry-pick all your changes
-# into the project-template repository immediately.
-#
-#######################################################################################################################
-
-include(CheckCXXCompilerFlag)
-CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)
-CHECK_CXX_COMPILER_FLAG("-std=c++0x" COMPILER_SUPPORTS_CXX0X)
-if(COMPILER_SUPPORTS_CXX11)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
-    set(${PROJECT_NAME}_CXX_FLAGS "${${PROJECT_NAME}_CXX_FLAGS} -std=c++11")
-    set(${PROJECT_NAME}_CMAKE_CXX_FLAGS "${${PROJECT_NAME}_CMAKE_CXX_FLAGS} -std=c++11")
-elseif(COMPILER_SUPPORTS_CXX0X)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
-    set(${PROJECT_NAME}_CXX_FLAGS "${${PROJECT_NAME}_CXX_FLAGS} -std=c++0x")
-    set(${PROJECT_NAME}_CMAKE_CXX_FLAGS "${${PROJECT_NAME}_CMAKE_CXX_FLAGS} -std=c++0x")
-else()
-    message(STATUS "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support. Please use a different C++ compiler.")
-endif()