Tidy up entity geometry stuff:

- Add a getCentre method for entities to GeometryUtils
- Replace getPositionEyes(0) with getPositionEyes(1) since it's more efficient, and by definition they must be the same
- Remove all the silly getEntityBoundingBox().minY stuff, this bug has been fixed since 1.8! (which begs the question: if it was considered a bug, how on earth did it go unfixed for that long?)
- A few other small things

src/main/java/electroblob/wizardry/item/ItemArtefact.java

@@ -609,7 +609,7 @@ public class ItemArtefact extends Item {
 									.pos(0, event.getEntity().height/2, 0).target(target).spawn(player.world);
 
 							ParticleBuilder.spawnShockParticles(player.world, target.posX,
-									target.getEntityBoundingBox().minY + target.height/2, target.posZ);
+									target.posY + target.height/2, target.posZ);
 						}
 
 						DamageSafetyChecker.attackEntitySafely(target, MagicDamage.causeDirectMagicDamage(player,
@@ -693,7 +693,7 @@ public class ItemArtefact extends Item {
 												.pos(0, event.getEntity().height/2, 0).target(target).spawn(world);
 
 										ParticleBuilder.spawnShockParticles(world, target.posX,
-												target.getEntityBoundingBox().minY + target.height/2, target.posZ);
+												target.posY + target.height/2, target.posZ);
 									}
 
 									DamageSafetyChecker.attackEntitySafely(target, MagicDamage.causeDirectMagicDamage(player,

src/main/java/electroblob/wizardry/item/ItemLightningHammer.java

@@ -210,7 +210,7 @@ public class ItemLightningHammer extends Item implements IConjuredItem {
 					if(hit.world.isRemote){
 						ParticleBuilder.create(Type.LIGHTNING).pos(hit.getPositionVector().add(0, hit.height / 2, 0))
 								.target(target).spawn(hit.world);
-						ParticleBuilder.spawnShockParticles(hit.world, target.posX, target.getEntityBoundingBox().minY + target.height / 2, target.posZ);
+						ParticleBuilder.spawnShockParticles(hit.world, target.posX, target.posY + target.height / 2, target.posZ);
 					}
 
 					//target.playSound(WizardrySounds.SPELL_SPARK, 1, 1.5f + 0.4f * world.rand.nextFloat());

src/main/java/electroblob/wizardry/item/ItemPurifyingElixir.java

@@ -59,7 +59,7 @@ public class ItemPurifyingElixir extends Item {
 
 			for(int i = 0; i < 20; i++){
 				double x = entity.posX + world.rand.nextDouble() * 2 - 1;
-				double y = entity.getEntityBoundingBox().minY + entity.getEyeHeight() - 0.5 + world.rand.nextDouble();
+				double y = entity.posY + entity.getEyeHeight() - 0.5 + world.rand.nextDouble();
 				double z = entity.posZ + world.rand.nextDouble() * 2 - 1;
 				ParticleBuilder.create(Type.SPARKLE).pos(x, y, z).vel(0, 0.14, 0).clr(0x0f001b)
 						.time(20 + world.rand.nextInt(12)).spawn(world);

src/main/java/electroblob/wizardry/item/ItemWand.java

@@ -847,7 +847,7 @@ public class ItemWand extends Item implements IWorkbenchItem, ISpellCastingItem,
 
 				if(player.world.isRemote){
 
-					Vec3d origin = new Vec3d(player.posX, player.getEntityBoundingBox().minY + player.getEyeHeight(), player.posZ);
+					Vec3d origin = player.getPositionEyes(1);
 					Vec3d hit = origin.add(player.getLookVec().scale(player.getDistance(event.getTarget())));
 					// Generate two perpendicular vectors in the plane perpendicular to the look vec
 					Vec3d vec1 = player.getLookVec().rotatePitch(90);