Trim performance (#451)

* Increase performance slightly when trimming.
If the chunk section is all one blocks (common in plotworlds) it'll be a nice little boost.

* Cache whether blocks are ticking or not. Greatly reduces the time required to create a palette

* collapse 5 lines to 2.

* Also apply to 14 and 15 for the numpties

* Cleanup
Actually ignore the exception - remove my debug print.
Remove double semi-colon

* Apparently 1.14/15 matter too still.

worldedit-core/src/main/java/com/boydti/fawe/jnbt/anvil/MCAChunk.java

@@ -549,6 +549,11 @@ public class MCAChunk implements IChunk {
         return isEmpty();
     }
 
+    @Override
+    public boolean trim(boolean aggressive, int layer) {
+        return hasSection(layer);
+    }
+
     @Override
     public CompoundTag getEntity(UUID uuid) {
         return this.entities.get(uuid);