This is a big API change, and it's probably not in it's ideal
shape right now. Physis makes a big assumption that the pool of
game data that you're reading from is in the compressed, SqPack
format like in retail. However, as the projects that use Physis
expand - so does the scope of data people want to punt into it.
For example, we have Icarus that makes it easy to read Excel data
but it can only do so through SqPack which makes it less useful in
scenarios where you want to read unpacked Excel modded files or
perhaps Excel data from the network.
So I created a Resource trait that GameData now implements (and
it's now called SqPackResource.) In a similar vain, Physis comes
with an UnpackedResource and a ResourceResolver to chain multiple
Resources together.
