OAK-1462 - Aggregate Index isn't usable in an osgi environment

Introducing LuceneIndexProviderService would register the LuceneIndexProvder. It would also track NodeAggregator and Analyzer and register it with LIP if found

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1601853 13f79535-47bb-0310-9956-ffa450edef68