Added private static final UID

By: durron597 <martin.jared@gmail.com>

paper-api/src/org/bukkit/event/EventException.java

@@ -1,7 +1,8 @@
 package org.bukkit.event;
 
 public class EventException extends Exception {
-    private final Throwable cause;
+	private static final long serialVersionUID = 3532808232324183999L;
+	private final Throwable cause;
 
     /**
      * Constructs a new EventException based on the given Exception

paper-api/src/org/bukkit/plugin/InvalidDescriptionException.java

@@ -5,7 +5,8 @@ package org.bukkit.plugin;
  * Thrown when attempting to load an invalid PluginDescriptionFile
  */
 public class InvalidDescriptionException extends Exception {
-    private final Throwable cause;
+	private static final long serialVersionUID = 5721389122281775894L;
+	private final Throwable cause;
 
     /**
      * Constructs a new InvalidDescriptionException based on the given Exception

paper-api/src/org/bukkit/plugin/InvalidPluginException.java

@@ -5,7 +5,8 @@ package org.bukkit.plugin;
  * Thrown when attempting to load an invalid Plugin file
  */
 public class InvalidPluginException extends Exception {
-    private final Throwable cause;
+	private static final long serialVersionUID = -8242141640709409542L;
+	private final Throwable cause;
 
     /**
      * Constructs a new InvalidPluginException based on the given Exception