Fix calling CombustEvent caused by enchantment

The CombustEvent created when an Entity attacks with a fire enchanted weapon
was never raised through the plugin manager. Thanks for pointing it out
EdGruberman!

src/main/java/net/minecraft/server/EntityHuman.java

@@ -844,6 +844,8 @@ public abstract class EntityHuman extends EntityLiving {
                 if (l > 0) {
                     // CraftBukkit start - raise a combust event when somebody hits with a fire enchanted item
                     EntityCombustByEntityEvent combustEvent = new EntityCombustByEntityEvent(this.getBukkitEntity(), entity.getBukkitEntity(), l*4);
+                    Bukkit.getPluginManager().callEvent(combustEvent);
+
                     if (!combustEvent.isCancelled()) {
                         entity.setOnFire(combustEvent.getDuration());
                     }