more flexible serial number handling in dnssec-signzone

[Jay Ford]

I found myself in need of more flexibility in the way dnssec-signzone handled 
SOA serial numbers, so I hacked in a way to have the new serial number 
generated by calling strftime(3) with a user-specified time format.  For 
example
    dnssec-signzone -N '%Y%m%d1' ...
will generate a serial number of the form yyyymmdd1 (e.g., 201010151).

The diff files for dnssec-signzone & its documentation relative to the
9.7.2-P2 version of BIND are available at (for now anyway):
    http://seatpost.its.uiowa.edu/bind_stuff

I'm a net guy not a programmer, so it's not the best code ever written & I
didn't increment any of the version headers, but it might be useful to some
anyway.

ISC folk:
    Please consider incorporating this or something similar into the stock
    dnssec-signzone.

________________________________________________________________________
Jay Ford, Network Engineering Group, Information Technology Services
University of Iowa, Iowa City, IA 52242
email: jay-ford at uiowa.edu, phone: 319-335-5555, fax: 319-335-2951