Bug fix: fragiles on top of dispensers no longer fall off

New feature: metadata / damage value differentiation in .craft files is
now supported. IE: you can make an airskiff that allows orange wool, but
not cyan wool. Also supported for flyblocks. To specify a metadata type,
put the number in quotes.

New feature: multiple flyblock block IDs. For example, you can specify a
flyblock that contains wood planks, wood stairs, and wood slabs. They
will all share the same pooled requirement. IE: half of the ship must be
wood, but it can be any kind of wood.