When checking for glew, don't fail if a working system version is not

found so we can fall back to the Externals version.

CMakeLists.txt

@@ -648,11 +648,11 @@ else()
 		if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
 			include(FindGLEW)
 		endif()
-		if(NOT GLEW_FOUND)
+		if(NOT GLEW_FOUND OR NOT GLEW_HAS_1_9_METHODS)
 			message("Using static GLEW from Externals")
 			add_subdirectory(Externals/GLew)
 			include_directories(Externals/GLew/include)
-		endif(NOT GLEW_FOUND)
+		endif()
 	endif()
 endif()