Basalt + better custom rocks

Avoid having classes for each type of rock, add generation conditions
from the Materials directly.

src/resources/assets/mmm/blockstates/materials/rock/basalt.json

@@ -0,0 +1,5 @@
+{
+    "variants": {
+        "normal": { "model": "mmm:materials/rock/basalt" }
+    }
+}

src/resources/assets/mmm/lang/en_US.lang

@@ -11,6 +11,7 @@ gui.mmm.tech.base.am.disabled=Deactivated
 tile.mmm.materials.rock.limestone.name=Limestone
 tile.mmm.materials.rock.chalk.name=Chalk
 tile.mmm.materials.rock.slate.name=Slate
+tile.mmm.materials.rock.basalt.name=Basalt
 
 tile.mmm.materials.ore.rock_salt.name=Rock Salt
 item.mmm.materials.stone.rock_salt.name=Salt Crystals

src/resources/assets/mmm/models/block/materials/rock/basalt.json

@@ -0,0 +1,6 @@
+{
+    "parent": "minecraft:block/cube_all",
+    "textures": {
+        "all": "mmm:blocks/materials/rock/basalt"
+    }
+}

src/resources/assets/mmm/models/item/materials/rock/basalt.json

@@ -0,0 +1,3 @@
+{
+    "parent": "mmm:block/materials/rock/basalt"
+}