Changes in the Deck Exchange

[Programmer]

I have made some changes to the way the Deck Exchange works, specifically regarding how it decides when to delete decks from the cache. The way it works now is that decks are kept in cache for fast download for three months after they are uploaded, OR REQUESTED AGAIN. Each time you download a deck you that deck will preserved in cache for at least a further three months. The effect of this should be that popular decks remain available longer. I hope it also means that more people will feel encouraged to leave comments about the decks now, given that if a deck is downloaded at least once every three months it never need disappear from the Exchange.