added hook_update_dependencies to make sure that any important discount updates go first if they are run during the same updatedb

removed a entity property load during rules rebuild that was loading every coupon at once; fixed discount UI form to handle large numbers of coupons properly

added custom settings for entity update batch size; replaced cache chear in update function with calls to field install functions

preventing transactions from being written twice for same order/coupon; ensured commerce discount is present for upgrade

supporting beta1 to beta2 update; fixed menu item type for conditions link; fixed coupon row lock function