Add AnnotationConfigApplicationContext constructor

Add AnnotationConfigApplicationContext constructor allow use of a
custom DefaultListableBeanFactory.
Support *Aware ImportSelectors

Implementations of Spring's ImportSelector interface may
now implement any of the following *Aware interfaces and have their
respective methods called prior to #registerBeanDefinitions:

 - BeanFactoryAware
 - BeanClassLoaderAware
 - ResourceLoaderAware
Add support for DeferredImportSelector

Add DeferredImportSelector interface that can be used to select imports
after all @Configuration beans have been processed.