SERVER-14056 Cross-DB renameCollection needs to call commitIfNeeded

Fixes regression introduced in 0abf27ae.

Before 0abf27a, renameCollection used a DBDirectClient to read objects
from the source namespace.  The call to DBClientCursor::next() would
issue a getmore after finishing each batch, which would reach a commit
point (in DBDirectClient::call()).  The port to the new collection
interface removed the use of DBDirectClient, which removed
renameCollection's commit point.
SERVER-13961 Remove thread-local write intents

This change makes all write intents go straight to the global write
intents list. Cleaning this up is necessary as a step to going to a
per-operation intents list, but it may cause more contention on the global
intents list.
SERVER-13961 Pass LockState to DBWrite and DBRead directly

This is part of the changes to move LockState be part of OperationContext
and not retrieved from TLS.
Revert "SERVER-13961 Pass LockState to DBWrite and DBRead directly"

This reverts commit 0672061deb58aac931912bed68d014247c581968.