Previously, we had WBFS and CISO which both returned an upper bound
of the size, and other formats which returned an accurate size. But
now we also have NFS, which returns a lower bound of the size. To
allow VolumeVerifier to make better informed decisions for NFS, let's
use an enum instead of a bool for the type of data size a blob has.

DTLX01 can be either a Freeloader or Action Replay, so it's
inappropriate to always use the same title and cover for it.

Needed for the disc mentioned in the previous commit.

SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.

Eliminates quite a bit of the PRI* macros used for handling 64-bit
values.