Sweatshop workers never become unproductive due to drops in local demand; they're assumed to be working for export.
This means sweatshops can be used as a way to protect the productivity of your menial workers.
Make menial productivity calculations more consistent; fixes a discontinuity where adding one single menial worker could drop your menial productivity by 40% or more.

Simplify "chooses own job" system.  Remove two-pass system (and the "2" state for `slave.choosesOwnAssignment`) and global variable, consolidate job-printing logic, fix a few bugs, and improve error handling.

Removes `$oldACitizens` global state variable.
Make sure `NCSYouthening` is defined on the player object.
A few typo corrections.
Migrates `reCitizenHookup` to use the same (more robust) FS key mechanism as `reMaleCitizenHookup`.
Fix some bad ledger entries.
Clean up migration of player fertility drugs from `fertDrugs`.
Some fixes for `RESS Gorging`.