(WIP) Rudimentary version of Wii IPC determinism.  Ported from my old udpnet branch.

This version always starts from a blank slate NAND.  Might not be complete.

Only the NAND moves, not the whole user folder.  You can still call the same function, if you actually want the user folder: e.g. the sysconf-settings relay will want to write to the real Wii folder if the configuration dialog is changed, regardless of whether a game is currently running in this mode.  But if you want the temporary folder, it's not in the user folder, so it doesn't go under GetUserPath.