We added using the bulk loader for for foreground index builds in WT with SERVER-16199. This ticket is for allowing the bulk loader for the collection documents as well.
Add support for bulk loading (with WiredTiger)
Collection and Database Cloner: Implement storage engine interface
create a cloneUnshardedCollections command for use in movePrimary
For uncapped collections, CollectionBulkLoaderImpl::insertDocuments should batch the documents and commits the batch in a single WriteUnitOfWork
[POC] Make Initial sync collection cloner to use wiredTiger Bulk-load api