Knuth updated DLX algorithm for new chapters

You have to weave this into a pretty format if you want to really ready it. I don't know if that is something I can legally just do and host somewhere, if it is, I'd be glad to.

Main callouts for me, are he tried his idea of not using left/right links for the rows and found it didn't actually save any time. Always fun to see him hit a surprise. (I had tried this, but assumed I just wasn't doing it right when I found no real difference.)

He also has a section where he mentions that he convinced himself one order of operations was not important, only to realize it was. I love that he is exploring it.