Upgraded to Spring Data Codd

Update AbstractRepositoryConfigurationSourceSupport to use the newly
introduced RepositoryConfigurationDelegate instead of effectively
reimplementing Spring Data Commons functionality which was prone to
changes in the API (code that wasn't considered to be API in the first
place).

Switch from implementing BeanClassLoaderAware to ResourceLoaderAware
to avoid having to set up a DefaultResourceLoader which should also
improve IDE integration.

Fixes gh-236