SpaceConfigurer now extends standard Closable interface

SpaceConfigurer already has a close method. Enhancing it to extend the standard Closable interface allows it to be used in a try-with-resources statement, for example:

try (SpaceConfigurer configurer = new EmbeddedSpaceConfigurer("foo")) {
GigaSpace gigaSpace = new GigaSpaceConfigurer(configurer).create();
}