Many people have helped develop \ifpacktwo{}, and we would like to acknowledge
their contributions here: Ross Bartlett, Tom Benson, Erik Boman, Joshua Booth,
Julian Cortial, Kevin Deweese, Jeremie Gaidamour, Paul Lin, Travis Fisher, Sarah
Osborn, Eric Phipps, and Paul Tsuji. Finally, Alan Williams did the original
port from \ifpack{} and was the original lead developer of \ifpacktwo{}.
