BZ-1147929 - Business central cannot be started on WebSphere due to CDI ...

...UnsatisfiedResolutionException on type SocialAdapterRepositoryAPI

several things to notice here:
- somehow PluginServicesImpl does not get the injection of MediaServletURI so I made it temporarily wrapped with Instance to not fail at deploy time
- SocialActivitiesEventObserver is listening for all events (Object event) and thus when being marked as @Dependant was receiving events for it was fully initialized and thus causing lots of issues. Not it's application scoped and is startup bean so it will be active as soon app starts
- @PostConstruct methods cannot throw checked exceptions

as far as I could test it works fine on both JBoss and WAS but since I don't know these features well please give it a look. At least with this application deploys on WAS so it does not block QE from doing tests.