version number updates for release 3.12.13

creating Ipopt/releases/3.12.12 from Ipopt/stable/3.12 (rev 2760)

creating Ipopt/releases/3.12.11 from Ipopt/stable/3.12 (rev 2728)

creating Ipopt/releases/3.12.10 from Ipopt/stable/3.12 (rev 2720)

creating Ipopt/releases/3.12.9 from Ipopt/stable/3.12 (rev 2707)

creating Ipopt/releases/3.12.8 from Ipopt/stable/3.12 (rev 2691)

creating Ipopt/releases/3.12.7 from Ipopt/stable/3.12 (rev 2683)

creating Ipopt/releases/3.12.6 from Ipopt/stable/3.12 (rev 2668)

creating Ipopt/releases/3.12.5 from Ipopt/stable/3.12 (rev 2655)

creating Ipopt/releases/3.12.4 from Ipopt/stable/3.12 (rev 2595)