Castle vault unlock price cap + Gem tier adjustment

The castle vault can get of pricey if you try to ugprade everything, so the price caps at 50 silver, 50 lumber, and 50 bricks.

Gem tiers also now are set to T1 for the first two, T2 for the next two, and T3 for the last two.

Build 0.5.11

• Castle Vault prices are now capped when they reach 50.

• Gem tiers updated, first two sets of gems are T1, next two are T2, last two are T3.

• Fixed an issue with storage discount not applying to the very first upgrade at 10 storage.

• Fixed Billy the Slime name issue in statistics section.