Soy: Extend shortSubject to 72 chars

The default wrap value is 72. Conform to that.

Change-Id: I6ca5824831a48e90e1b697fb153102c7e38adbd8
diff --git a/Documentation/config-mail.txt b/Documentation/config-mail.txt
index 1adc8d9..af2bd98 100644
--- a/Documentation/config-mail.txt
+++ b/Documentation/config-mail.txt
@@ -201,7 +201,7 @@
 
 $change.shortSubject::
 +
-The subject limited to 63 characters, with an ellipsis if it exceeds that.
+The subject limited to 72 characters, with an ellipsis if it exceeds that.
 
 $change.ownerEmail::
 +