Implemented new Anvil saving format, fixed old chunk saving format.

- Added 'Chunk' Interface.
 - Moved old 'Chunk' to 'OldChunk' and replaced dynamic world height reference with '128.
 - Added 'AnvilChunk' implementing the new anvil chunk format.
 - Added temp fixes to FileMcRegionChunkStore.java, TrueZipMcRegionChunkStore.java and ZippedMcRegionChunkStore.java too allow them to read .mca files.
 - Added the new 'IntArrayTag' since the new heightmap tag wasn't recognized.
 - Moved 'getChildTag' to 'NBTUtils'.

src/main/java/com/sk89q/jnbt/NBTInputStream.java

@@ -199,6 +199,13 @@ public final class NBTInputStream implements Closeable {
             }
 
             return new CompoundTag(name, tagMap);
+        case NBTConstants.TYPE_INT_ARRAY:
+            length = is.readInt();
+            int[] data = new int[length];
+            for (int i = 0; i < length; i++) {
+                data[i] = is.readInt();
+            }
+            return new IntArrayTag(name, data);
         default:
             throw new IOException("Invalid tag type: " + type + ".");
         }