Poor Mint choices

[bilts]

The AI should be more careful about which treasures it chooses to play when buying Mint:

== Mint AI's turn 4 ==
Mint AI plays Silver.
Mint AI plays Quarry.
Mint AI plays Copper.
Mint AI plays Copper.
Mint AI plays Copper.
Coins: 6, Potions: 0, Buys: 1
Mint AI buys Mint.
...trashing a Copper.
...trashing a Copper.
...trashing a Copper.
...trashing a Quarry.
...trashing a Silver.
(Mint AI shuffles.)
Mint AI draws 5 cards: [Copper, Copper, Mint, Copper, Estate].