More code dealing with instance and global parameter semantics. I finally have a reasonable model of inheritance and semantics implemented, not perfect from a language-theoretic point of view, but works well without having to rewrite every bit of parameter-handling code in acs-core.
Fixed up the apm parameter stuff to the point where I can at least register and unregister, and cache values of, global parameters. There's some really funky code here, I also took the time to have the unregister code use the unregister API in PL/[pg]SQL rather than roll its own.