krb5: new tag krb5-1.12.5-final

[Tom Yu]

A new lightweight tag "krb5-1.12.5-final" has been created in the krb5
repository for the following commit:

commit a15935b91639a4c97b256c2575de83d68b807137
Author: Tom Yu <tlyu at mit.edu>
Date:   Mon Dec 14 16:23:34 2015 -0500

    Updates for krb5-1.12.5