Metal bars & craftable ancient bars (#218)

[M-W-K]

Implement bar blocks for brass, thaumium, and void metal using textures from #218.
Additionally makes ancient bars craftable with 2 gold ingots and 4 ancient stone to 8 bars.

[TheCodex6824]

The new bars seem to work well except that there are some holes in them when they are standing on their own (the "post" state). The texture UVs of the new bars probably just need to be shifted or tweaked to match the textures.

Also, what do you think about brass ingots in the ancient bars recipe instead of gold? I think the color is a lot closer.

[M-W-K]

I did see the holes, but I decided to leave them be, partially out of lazyness, partially because it provides a certain visual flair that builders might want to make use of.
While brass is a closer color, I chose gold because it's the only ingot, in minecraft + thaumcraft + thaumic augmentation, that doesn't have an associated bar if this change goes through.