Attempt to fix Vending glitch

- set_machine is now only fired AFTER the electrify check to ensure a shocked user is properly registered as no longer interacting with the machine
- Menu does not show up if you get electrified on an electrified dispenser. If you resist the electrify check (for instance with insulated gloves) this will not change anything
- If the wire menu is up, it will need to be closed manually as usual

Should fix #1715