Replace Achievements with Advancements

- Advancements are now in JSON files, converted by the included migration script.
- WizardryAdvancementTrigger is a generic achievement trigger that can be reused throughout the code to trigger custom advancements not covered by the JSON conditions.
- Plus some other small and obvious fixes.

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

@@ -1,17 +1,16 @@
 package electroblob.wizardry.item;
 
-import java.util.List;
-
 import electroblob.wizardry.Wizardry;
 import electroblob.wizardry.advancement.AdvancementHelper;
 import electroblob.wizardry.advancement.AdvancementHelper.EnumAdvancement;
 import electroblob.wizardry.constants.Constants;
 import electroblob.wizardry.constants.Element;
+import net.minecraft.client.model.ModelBiped;
+import net.minecraft.client.resources.I18n;
+import electroblob.wizardry.registry.WizardryAdvancementTriggers;
 import electroblob.wizardry.registry.WizardryTabs;
 import electroblob.wizardry.spell.Petrify;
 import electroblob.wizardry.util.WizardryUtilities;
-import net.minecraft.client.model.ModelBiped;
-import net.minecraft.client.resources.I18n;
 import net.minecraft.client.util.ITooltipFlag;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.EntityLivingBase;
@@ -30,6 +29,9 @@ import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
 import net.minecraftforge.fml.relauncher.Side;
 import net.minecraftforge.fml.relauncher.SideOnly;
 
+import javax.annotation.Nullable;
+import java.util.List;
+
 @Mod.EventBusSubscriber
 public class ItemWizardArmour extends ItemArmor implements ISpecialArmor {
 
@@ -233,7 +235,7 @@ public class ItemWizardArmour extends ItemArmor implements ISpecialArmor {
 				}
 			}
 			// If it gets this far, then all slots must be wizard armour, so trigger the achievement.
-			AdvancementHelper.grantAdvancement(player, EnumAdvancement.armour_set);
+			WizardryAdvancementTriggers.armour_set.triggerFor(player);
 		}
 	}