MB-10326: Use poll instead of select

Win32 supports WSAPoll as of vista

Change-Id: I8c43cf5da153c47d2f8d52145a2639e89ae899a5
Reviewed-on: http://review.couchbase.org/34226
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>