Unwrap Event Exceptions

This was a useless exception wrapper that ends up making
stack traces harder to read as well as the JVM cutting off
the important parts

Nothing catches this exception, so its safe to just get rid
of it and let the REAL exception bubble down

Spigot-API-Patches/0031-Add-MetadataStoreBase.removeAll-Plugin.patch

@@ -0,0 +1,41 @@
+From 28cef08075786587ecc702ad3dab4bc06d3ce624 Mon Sep 17 00:00:00 2001
+From: Aikar <aikar@aikar.co>
+Date: Tue, 16 Jul 2013 21:26:50 -0400
+Subject: [PATCH] Add MetadataStoreBase.removeAll(Plugin)
+
+So that on reload, metadata will be cleared
+
+diff --git a/src/main/java/org/bukkit/metadata/MetadataStoreBase.java b/src/main/java/org/bukkit/metadata/MetadataStoreBase.java
+index 64c0f0a7..6da6abd8 100644
+--- a/src/main/java/org/bukkit/metadata/MetadataStoreBase.java
++++ b/src/main/java/org/bukkit/metadata/MetadataStoreBase.java
+@@ -124,6 +124,26 @@ public abstract class MetadataStoreBase<T> {
+         }
+     }
+ 
++    /**
++     * Removes all metadata in the metadata store that originates from the
++     * given plugin.
++     *
++     * @param owningPlugin the plugin requesting the invalidation.
++     * @throws IllegalArgumentException If plugin is null
++     */
++    public void removeAll(Plugin owningPlugin) {
++        Validate.notNull(owningPlugin, "Plugin cannot be null");
++        for (Iterator<Map<Plugin, MetadataValue>> iterator = metadataMap.values().iterator(); iterator.hasNext(); ) {
++            Map<Plugin, MetadataValue> values = iterator.next();
++            if (values.containsKey(owningPlugin)) {
++                values.remove(owningPlugin);
++            }
++            if (values.isEmpty()) {
++                iterator.remove();
++            }
++        }
++    }
++
+     /**
+      * Creates a unique name for the object receiving metadata by combining
+      * unique data from the subject with a metadataKey.
+-- 
+2.20.1
+