Add clarification of email notifications in documentation

Update the documentation to clarify the cases in which the user
will not receive email notifications.

Change-Id: Iab4ee292eeeecca05b8cbfd3e2c365743cb3141f

Documentation/user-notify.txt

diff --git a/Documentation/user-notify.txt b/Documentation/user-notify.txt
index 711d1ac..558dcb5 100644
--- a/Documentation/user-notify.txt
+++ b/Documentation/user-notify.txt
@@ -22,6 +22,14 @@
 change notifications to specific subsets, for example `branch:master`
 to only see changes proposed for the master branch.
 
+Notification mails for new changes and new patch sets are not sent to
+the change owner.
+
+Notification mails for comments added on changes are not sent to the user
+who added the comment unless the user has enabled the 'CC Me On Comments I
+Write' option in the user preferences.
+
+
 Project Level Settings
 ----------------------