Reduces visibility of internal fields/methods

Reduces the visibility of all fields to private and create setters/getters
when necessary. Exceptions are fields with GuiSync as these need to be
public.

Reduces the visibility of internal methods to private/protected/default when possible.

src/main/java/appeng/me/storage/CellInventoryHandler.java

@@ -108,7 +108,7 @@ public class CellInventoryHandler extends MEInventoryHandler<IAEItemStack> imple
 	@Override
 	public ICellInventory getCellInv()
 	{
-		Object o = this.internal;
+		Object o = this.getInternal();
 
 		if( o instanceof MEPassThrough )
 		{