krb5: new tag krb5-1.12-alpha1

[Tom Yu]

A new lightweight tag "krb5-1.12-alpha1" has been created in the krb5
repository for the following commit:

commit 4f1952a815aad3012acf5b7d9b3d82bd3c80f3d6
Author: Tom Yu <tlyu at mit.edu>
Date:   Fri Oct 11 14:47:39 2013 -0400

    Updates for krb5-1.12-alpha1