Daravind/Catalog metrics storage

CatalogMetricsStorage

1) Added support to Metrics Service to store metrics in a Catalog
2) CatalogMetricsStorage only writes to Catalog from 1 (background) thread by using a ConcurrentQueue
3) Also, using 'ShouldUseDBAndCatalog' setting, metrics may be written both to DB and Catalog
4) Following settings are supported as well
     i) IsLocalCatalog - uses filesystem
     ii) CatalogPageSize and CatalogItemPackageStatsCount to determine how the Catalog is built
Okay - in the meantime, you can delete the content files that came from the package so they aren't in the project since we're not using them.