Fixing placement bugs with BlockChestTFC

Fixes #536.

Also, allows chests of differing types to be placed next to each other
with no limitations. Chests of the same type are accurately checked for
validity before placing. Inventories properly handle looking for
neighbor chests of same type only.
Fixing dropping correct chest item
Merge pull request #537 from mabrowning/ChestFix

Chest bugfix and Feature enhancement