Move commonly used API systems to a plugin based system

Create a class that implements IBloodMagicPlugin and annotate it with
`@BloodMagicPlugin`. The `register` method will be called during init.

Currently implemented systems:
- Blacklisting
  - Teleposer
  - Teleposer (entity)
  - Transposition
  - Well of Suffering
  - Green Grove
- Setting sacrificial values
- Adding altar components

src/main/java/WayofTime/bloodmagic/entity/mob/EntityMimic.java

@@ -35,7 +35,7 @@ import net.minecraft.world.EnumDifficulty;
 import net.minecraft.world.World;
 import WayofTime.bloodmagic.block.BlockMimic;
 import WayofTime.bloodmagic.entity.ai.EntityAIMimicReform;
-import WayofTime.bloodmagic.registry.RegistrarBloodMagicBlocks;
+import WayofTime.bloodmagic.core.RegistrarBloodMagicBlocks;
 import WayofTime.bloodmagic.tile.TileMimic;
 
 public class EntityMimic extends EntityDemonBase

src/main/java/WayofTime/bloodmagic/entity/mob/EntitySentientSpecter.java

@@ -50,7 +50,7 @@ import WayofTime.bloodmagic.entity.ai.EntityAIOwnerHurtByTarget;
 import WayofTime.bloodmagic.entity.ai.EntityAIOwnerHurtTarget;
 import WayofTime.bloodmagic.entity.ai.EntityAIRetreatToHeal;
 import WayofTime.bloodmagic.item.soul.ItemSentientBow;
-import WayofTime.bloodmagic.registry.RegistrarBloodMagicItems;
+import WayofTime.bloodmagic.core.RegistrarBloodMagicItems;
 
 public class EntitySentientSpecter extends EntityDemonBase
 {

src/main/java/WayofTime/bloodmagic/entity/projectile/EntityBloodLight.java

@@ -1,7 +1,7 @@
 package WayofTime.bloodmagic.entity.projectile;
 
 import WayofTime.bloodmagic.api.Constants;
-import WayofTime.bloodmagic.registry.RegistrarBloodMagicBlocks;
+import WayofTime.bloodmagic.core.RegistrarBloodMagicBlocks;
 import io.netty.buffer.ByteBuf;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.EntityLivingBase;