1.7.x refactoring

Ok, looks like 1.7.9 finally fixes "the" major bug(s) I introduced with the movement refactoring in 1.7.5. I guess I won't know for sure if it was one of the 1.7.8 changes unless I let it fill out its battles, but it started off tanking pretty hard and the wrong GFs in the flattener (fixed in 1.7.9) is exactly the type of thing I thought would be the problem. (I switched to precise intersection in the flattener, since it was free with the new wave processing, but copied a couple lines from the gun that also used precise MEA GFs.) I'm really happy to have the wave interpolation and bullet shadow fixes too, though, and wonder if they're the reason 1.7.9 is undefeated (that or luck).

Regardless, I'm happy I can move on to the rest of the movement refactor. There's still quite a lot to do. :-) It's amazing I can refactor or rewrite every 1-2 years, and every time, the previous code seems so terrible...