Added ToFacets and ToFacetsLazily for LuceneQuery

To ease use of Facets within a LuceneQuery, I added the extensions of
ToFacets for convenience. Added additional tests around these new
extensions - all passing.

Was not sure how to get IAsyncDocumentQuery into  ( (
RavenQueryInspector<T> )queryable ) so did not implement ToFacetsAsync.
If you would like to comment and indicate the right path, I could add
that before you commit this pull request.
RavenDB-885 Periodic Backup": Bug when loading from saved data when using s3
RavenDB-884 SQL Replication Entity Name drop box on small resolution
RavenDB-880 TransitiveReplicationBehavior isn't set properly in the UI
RavenDB-875 IAsyncDatabaseCommands missing async equivalent of IDatabaseCommands.Head
Merge branch 'master' of github.com:ayende/ravendb
Fixing an issue where rollback a transaction using optimistic concurrency would fail
Merge branch '2.01' of git://github.com/DanielDar/ravendb
Levenshtein should be before JaroWinkler in the UI
Add the ability to setup periodic backup to local path in the studio
RavenDB-806 TimeSpan values don't index well
Adding passing test
RavenDB-846 Put Trigger can't use Last-Modified date
Merge branch 'master' of github.com:fitzchak/ravendb
Add suggestion support in the UI
Put the suggestion on the right
RavenDB-888 Import using an CSV file should create the document's Raven-Entity-Name value in the pluralize form.
Generate also the symbols. RavenDB-862 Upload the PDBs files to symolsource.org
Merge branch 'master' of github.com:fitzchak/ravendb
Making sure that backup logs are going to the proper db