Basic infrastructure for supporting annotation based auditing configuration.
Introduces AuditingBeanDefinitionRegistrarSupport for store specific auditing configuration enhancements. An AuditorAware instance is wired into the Auditing handler automatically if it's present in the ApplicationContext. The auditorAwareRef attribute of the enabling annotation can be used to disambiguate in case multiple AuditorAware instances are present in the configuration.
Original pull requests: #26, #53.
We're not manually converting the DateTime instance into the user field type but delegate to a ConversionService instance. This will allow us to automatically adhere to enhancements in conversion capabilities to the DefaultConversionService.
