Fix docs mising Search permission for example.

The

  All users may only view and edit issues, files and messages they create

example was missing the addition of Search permission. The example
predates the existence of the Search permission.

Author: rouilj

doc/customizing.txt

@@ -5786,12 +5786,19 @@ for the "issue", "file" and "msg" classes with the following::
         return check
     for cl in 'issue', 'file', 'msg':
         p = db.security.addPermission(name='View', klass=cl,
-            check=checker(cl))
+            check=checker(cl),
+            description='User can view only if creator.')
         db.security.addPermissionToRole('User', p)
         p = db.security.addPermission(name='Edit', klass=cl,
-            check=checker(cl))
+            check=checker(cl),
+            description='User can edit only if creator.')
         db.security.addPermissionToRole('User', p)
         db.security.addPermissionToRole('User', 'Create', cl)
+    # This allows the interface to get the names of the properties
+    # in the issue. Used for selecting sorting and grouping
+    # on the index page.
+    p = db.security.addPermission(name='Search', klass='issue')
+    db.security.addPermissionToRole ('User', p)
 
 
 Moderating user registration