Backend Finalization

TODO:
 - Listener implementations
 - Spell tome, book, and wand items
 - Persistent data storage
 - Configurable values
 - Custom spells

src/main/java/app/simplexdev/arcanumocculta/spell/effect/FireballEffect.java

@@ -0,0 +1,12 @@
+package app.simplexdev.arcanumocculta.spell.effect;
+
+import app.simplexdev.arcanumocculta.base.effect.AbstractSpellEffect;
+import org.bukkit.potion.PotionEffectType;
+
+import java.time.Duration;
+
+public class FireballEffect extends AbstractSpellEffect {
+    public FireballEffect(Duration duration, float amplifier) {
+        super(duration, amplifier, PotionEffectType.HARM);
+    }
+}