SERVER-14668 Remove unused includes in client.h and curop.h

Having these extra includes caused large portion of the code to be rebuilt
for changes to relatively standalone headers.
SERVER-14668 Distlock constants to enums and fix some includes

The macros were conflicting with LockManager enums, which are in different
namespaces (LOCK_TIMEOUT in particular).
SERVER-14745 Remove WritebackListener

Remove writeback on the shard side.
SERVER-14745 Remove WritebackListener

Merge d_logic in to d_state
Merge remote-tracking branch 'upstream/master'