* The SpringApplicationBuilder was registering the parent context initializer
twice (not really a problem, but confusing if you are debugging).
* ParentContextApplicationContextInitializer itself should have been
checking that the current context is not the parent
* The EventPublishingRunListener as a result needs to call
setApplicationContext on any listeners that are AplicationContextAware
* ParentContextCloserApplicationListener can ensure that there is
only one of its kind per application context by implementing hashCode
and equals
Fixes gh-1142
999748bdab