p4wn.js allow make castling under check
"rnb1r1k1/ppp2ppp/8/8/2PN4/2Nn4/P3BPPP/R3K2R w KQ - 5 14"
Fix castling under check from certain knight positions (github bug #3)
Another one found by Ivan Yelizariev. The patch is faily self
explanitary: the check for the knight on the third row to the left was
neglected while the knight to the right was checked twice.
Fixed in commit 7a3b428.
This missed checks were for knights two rows out and to the queen side. There were two lines with "+1" whereas one of then needs to be "-1".
Well spotted, Ivan, and thanks again.