Increased PKG Size Limit

[it-misha]

I have modified pkgrip.c to have a larger file size limit. The pkg size limit pointer has increased from a 32-bit uint to a 64-bit uint. The extraction progress readout has been updated to match. It's not pretty in the slightest, but it can now handle files larger than 4 GB with no fuss.

I have not fully tested the effects of this change in depth. All I know is that it works for its intended purpose with files up to 16 GB in size.