Googletest export

Clarify build system support - CMake and automake community supported

PiperOrigin-RevId: 245821927
diff --git a/CMakeLists.txt b/CMakeLists.txt
index afe7959..00fdeee 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,3 +1,6 @@
+# Note: CMake support is community-based. The maintaners do not use CMake
+# internally.
+
 cmake_minimum_required(VERSION 2.8.8)
 
 project(googletest-distribution)