Spell hierarchisation and refactoring, plus miscellaneous renaming and minor refactoring

- Adds new generic spell superclasses which aim to group spells such that duplicate code is eliminated, and functions standardised, as much as possible.
- Removes numerous spell classes which are no longer required as a result of this change, and replaces them with instances of the relevant generic spell classes.
- Changes the remaining spell classes to fit with the new system, mostly by having them extend the generic spell classes.
- Completes the transfer of particle spawning to the ParticleBuilder system.

src/main/java/electroblob/wizardry/client/renderer/RenderDecay.java

@@ -44,7 +44,7 @@ public class RenderDecay extends Render<EntityDecay> {
 
 		GlStateManager.rotate(-90, 1, 0, 0);
 
-		float scale = 2 * Math.min(1, (float)(EntityDecay.LIFETIME - entity.ticksExisted) / 50f);
+		float scale = 2 * Math.min(1, (float)(entity.lifetime - entity.ticksExisted) / 50f);
 
 		GlStateManager.scale(scale, scale, scale);