When life gives you lemons, make lemonade. Or in Bumbershoot's case, when headliners Ani DiFranco and Devo both cancel, scramble like mad and book Iggy and The Stooges and Elvis Costello in their places. Whee! At least on the former; we're a mite wary of the latter. And as a bonus, the Stooges, short a bass player, are touring this summer with none other than Mike Watt. The lineup (as it stands now--who knows who......