[suggestion] Dust should not have EMC

[TFC-343]

One of the most used machine set ups in tekkit is a macerator leading into a furnace, letting the dusts created from ingots have their own EMC removes half of this and makes the full set up wasteful. I think that most dusts (apart from maybe ones like bronze) shouldn't have their own emc and the ingot version should be the only part with its own emc.

[xJon]

I understand the rationale, although there's also logic for them to have an EMC as it's the same material. I prefer to keep the status quo of some dusts having an EMC value and some not, mostly matching the Tekkit Classic's behaviour.