Better passed pawns
A little less restrictive about endgame
Oops
Add pseudolegal moves to xboard.c

Trying to find a movegen bug with this position:
setboard 4Qb2/6kp/5qp1/1p3p2/p1pR4/6P1/5P1P/6K1 w KQkq - 0 1
(e1c1 isn't a legal move!)
Add comment about castling rights

Found this a few hours ago and went home, should note the source of the
mystery bug from earlier.