5th gen wing trade

[Shinigami l0_0l]

since inter-changing wings are allowed, let's make it easier for the GMs by adding a script similar to the upgrade process that will allow a player to exchange his/her gen5 wings

the logic should not be hard, most of the script will be a copy of the already-existent upgrade process where wing+voucher = higher lvl wing

[GM-Pandora]

Not sure we want to add this to the npc, when the new 5th gen wing came out we did wing changing, it was supposed to last a few months, but we kept doing it for players. Now we only do it at toh, but the original plan was to eventually stop providing this, at any rate, we'll see when we next update the npc, maybe.