added ClassLoader to JPAManager class
added ClassLoader to Ejb3ConfigurationImpl class
added method for loading of collection of classes to LibraryLoader class
improved BeanLoader to use costom ClassLoader for connection loader
improved JPAManager class
added connection configuration with specific class loader
improved class loader for connections
improved class loader passing to connection configuration
improved JPAManager.Builder for class loader passing
improved Ejb3ConfigurationImpl.Builder for ClassLoader passing