Consider removing some intermediates

[KiwiHawk]

Can we remove some intermediates? To reduce clutter.

• Remove Stone pipes so we have just two T1 pipes
• Remove Copper tungsten pipes so we have just two T5 pipes
• Remove Ceramic bearings so we have just 1 T4 bearing

Tier	Pipe A	Pipe B	Gear A	Gear B	Bearing
1	Iron	Copper	Iron
2	Bronze	Steel	Steel		Steel
3	Plastic	Aluminium	Cobalt Steel		Cobalt Steel
4	Brass	Ceramic	Brass	Titanium	Titanium
5	Tungsten	Nitinol	Tungsten	Nitinol	Nitinol

This assumes that #585 has been completed.