Fix broken White Card discard.
Fix broken White Card discard.

Firstly I was consuming an array in a subroutine, leaving it empty.

Secondly when I did preserve its contents, I had confusion over
arrayref-within-arrayref that meant the code was completely bogus.

I've now made this work and made it a little clearer.

domcleal/pah-irc,jfautley/pah-irc,grifferz/pah-irc,jshholland/pah-irc