Makes more machines require the previous tier to upgrade, similar to Assembling Machines.

Currently modifies:
- Inserter (requires burner)
- Steel/Electric Furnace (stone->steel->electric)
- Submachine Gun (requires pistol)
- Combat Shotgun (requires shotgun)
- Heavy/Modular/Power Armour (light->heavy->modular->mk1->mk2)
- Heat Exchanger (requires boiler)
- Steam Turbine (requires steam engine)

Costs are auto-modified to require less ingredients where possible (identical ingredients, plus detection for iron->steel and stone->brick).
For instance Inserter only requires an electric circuit as Burner Inserter requires an iron plate and iron gear.