SERVER-11178: first cut at IndexCatalog::createIndex
SERVER-11178: moving all index creation logic into IndexCatalog
SERVER-11178: move _id key fixing into IndexCatalog
SERVER-11178: remove prepareToBuildIndex, and have pdfile call into IndexCatalog for creating indexes
SERVER-11178: move ensureHaveIdIndex from bare to inside IndexCatalog
SERVER-11178: remove index_update.h from places its not needed (most)
SERVER-11178: rename index_update. to catalog/index_create.
SERVER-11178: refactor index_create to not use Cataloghack
SERVER-11294: create extent by default line we did in 2.4
SERVER-11178: move more CatalogHack calls to IndexCatalog
SERVER-11178: remove unused variable from old index_update