MB-25912 - cbdatasource worker that can't connect should kick
MB-25912 - cbdatasource worker that can't connect should kick

In the case that a worker goroutine can't successfully connect to a
couchbase node (because the node is down and perhaps failed-over),
that worker should kick the refreshClusterCh, which then ought to grab
a fresh cluster map.

Change-Id: I0e187b0dc102fe41fdbe04528b75b8860ec1369f
Reviewed-on: http://review.couchbase.org/83057
Tested-by: Steve Yen <ef850f73f7832052d3c6d9b5ddd3a1716d9a57f1@gmail.com>
Reviewed-by: abhinav dangeti <d73ef2279de6577f7bf081737ee47554bbb7dc82@couchbase.com>
Well-Formed: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

couchbase/go-couchbase