Main changes included:
1) Upgrade handling code can now handle an arbitrary number of upgrades.
2) Compatibility code to move upgrade items to the new upgrade inventory.
3) Registrations (power requirement tables, etc.) were updated so they no longer assume a fixed upgrade size.
4) Wrench registrations include the new inventory name.
The changes that this covers are that the alloy furnaces now have one
"src" inventory instead of a "src" and "src2"; that the tool workshop
is now MV; and the existence of MV compressor, extractor, and centrifuge.
