Fix improper caching causing duplications, closes #10

* Implemented a universal cache for loaded players
* Reworked a significant amount of my API additions
* Simplified join/quit handling
* Cleaned up ISpecialEnderChest/ISpecialPlayerInventory implementations
* Fixed OpenInv.* permission not granting access to commands

src/main/java/com/lishid/openinv/internal/ISpecialPlayerInventory.java

@@ -23,14 +23,23 @@ public interface ISpecialPlayerInventory {
 
     public Inventory getBukkitInventory();
 
-    public boolean inventoryRemovalCheck(boolean save);
-
+    /**
+     * Sets the Player associated with this ISpecialPlayerInventory online.
+     * 
+     * @param player the Player coming online
+     */
     public void setPlayerOnline(Player player);
 
     /**
      * Sets the Player associated with this ISpecialPlayerInventory offline.
-     * 
-     * @return true if the ISpecialPlayerInventory is eligible for removal
      */
-    public boolean setPlayerOffline();
+    public void setPlayerOffline();
+
+    /**
+     * Gets whether or not this ISpecialPlayerInventory is in use.
+     * 
+     * @return true if the ISpecialPlayerInventory is in use
+     */
+    public boolean isInUse();
+
 }