Make IndexPopulationJob log label names and property key names instead of ids.

o Hooking TokenNameLookupProvider (formerly: KeyNameLookupProvider) into IndexingService
  that is constructed in IAGD and passed on via NeoStoreXaDataSource and
  also made available from Kernel because that is where it should live eventually
o Renaming methods to match the Kernel API naming scheme
o Introduce LogMode utility
o Extract TokenNameLookupProvider interface from implementation
o Fix LuceneIndexRecoveryIT
Cleaning up error handling of FlippableIndexProxy