Drop support for MSVC versions older then 2013 with CMake

We get too many complaints about breakage and we intend to drop older versions soon anyway.

CMakeLists.txt

@@ -956,6 +956,12 @@ elseif(WIN32)
 	add_definitions(-DWIN32)
 
 	if(MSVC)
+
+		# drop support for older MSVC
+		if(MSVC_VERSION VERSION_LESS 1800)
+			message(FATAL_ERROR "MSVC versions older then 2013 are no longer supported")
+		endif()
+
 		set(PLATFORM_LINKLIBS ws2_32 vfw32 winmm kernel32 user32 gdi32 comdlg32 advapi32 shfolder shell32 ole32 oleaut32 uuid psapi)
 
 		# MSVC11 SDL is not hard linked to dxguid.lib