Given that Spring Boot uses java config accross the board, a new `value`
attribute is now aliased to the existing `classes` attribute such that
one could write the following:
@SpringApplicationConfiguration(MyConfig.class)
public class MyTest {}
Closes gh-3635
We can't easily solve the problem by not allowing Spring Security to
eagerly instantiate everything, but we can be defensive about data.sql
and make sure it is executed even if the listener isn't yet registered.
Fixes gh-1386
