Mark support for git protocol v2 as experimental

We don't have any tests for this yet.

Change-Id: I262a805be9a03bdbc7af3261d1f0a46af6a158d8
Signed-off-by: Edwin Kempin <ekempin@google.com>
diff --git a/Documentation/config-gerrit.txt b/Documentation/config-gerrit.txt
index d71e39b..df9c07d 100644
--- a/Documentation/config-gerrit.txt
+++ b/Documentation/config-gerrit.txt
@@ -3824,6 +3824,10 @@
 
 [[receive.enableProtocolV2]]receive.enableProtocolV2::
 +
+[NOTE]
+Support for Git protocol version 2 is still experimental. Do not use it in
+production!
++
 Enable support for git protocol version 2.
 +
 When this option is enabled, clients may send upload pack using git