This updates three major crates we use to the latest version with all of
their API changes, and the others too. Notably, this removes the Syn v1
dependency thanks to binrw 0.15 switching to Syn v2.
I wanted to add armory chest support but the current state of the
inventory was a little frustrating. Adding new containers was too
difficult, so I made the system *even more* generic and easier to use. I
have also split it up into it's own module with a nicer file layout.
Oh yeah, and armory chest works too now.
