Renamed Blocks and Minor Changes

Renamed block 1973:1 to Ancient Fabric. Renamed block 220 to Eternal
Fabric. I assigned new names so that we didn't need to use the long ones
we had before (e.g. "Fabric of Reality Permanent/Pushable"). Also
removed unused imports from various classes along the way.

StevenDimDoors/mod_pocketDim/blocks/BlockRift.java

@@ -5,7 +5,6 @@ import java.util.Random;
 import net.minecraft.block.BlockContainer;
 import net.minecraft.block.material.Material;
 import net.minecraft.client.renderer.texture.IconRegister;
-import net.minecraft.item.Item;
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.util.AxisAlignedBB;
 import net.minecraft.util.MathHelper;