_unlink as opposed to unlink for windows

Change-Id: I40a74c0942594cf48dfbbd3406dc935a4dbfbd35
Reviewed-on: http://review.couchbase.org/40280
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Reviewed-by: Sundararaman Sridharan <sundar@couchbase.com>
Tested-by: abhinav dangeti <abhinav@couchbase.com>
MB-11876 Check for new priority buckets after wakeup

If threads do not check for the presence of newly registered
buckets, then a rare race condition can happen where a thread
is unaware of the presence of a low priority bucket and keeps
continously checking the high priority Q which has no work.
This would block normal shutdown

Change-Id: Ic59ccbed69c205251e7897f349445d8982ec7be5
Reviewed-on: http://review.couchbase.org/40311
Tested-by: Sundararaman Sridharan <sundar@couchbase.com>
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Tested-by: Chiyoung Seo <chiyoung@couchbase.com>
MB-11299: Properly send the snapshot start and end seqnos

Currently we always set the snapshot start and end seqno to be the
same as the start seqno. This is incorrect if we recently were
disconnected and need to resume from a partial snapshot.

Change-Id: I7c9430e0b24ef01cc427cb03b518f4c41a55d875