moved capi ssl service to ns_couchdb

Because it belongs to ns_couchdb.

Otherwise if enterprise edition is enabled we try to spawn capi ssl
endpoint in ns_server and crash.

Change-Id: I29e708b8828203df02fb5c2fe164a8598d9ca820
Reviewed-on: http://review.couchbase.org/42430
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Artem Stemkovski <artem@couchbase.com>
returned capi_frontend:task_status_all/0

Otherwise common capi debugging endpoint (/_active_tasks) doesn't
work.

Change-Id: Ifc38e48cd9eea397167f854384b044fb76ff30a4
Reviewed-on: http://review.couchbase.org/42431
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Artem Stemkovski <artem@couchbase.com>