Implementation of the EntityDamage*Events.

A new event EntityDamageByProjectileEvent was created. EntityDamageByProjectileEvent
adds the ability to get the projectile entity (such as an egg) and also set if
the projectile 'bounces'. New interfaces were created to facilitate all kinds
of projectile entities. Changes were made to facilitate the new event, and
enable other events, for plugins and event listeners.

By: Andrew Ardill <andrew.ardill@gmail.com>

paper-api/src/main/java/org/bukkit/entity/Entity.java

@@ -9,7 +9,7 @@ import org.bukkit.World;
  */
 public interface Entity {
     /**
-     * Gets the entitys current position
+     * Gets the entity's current position
      *
      * @return Location containing the position of this entity
      */