MB-8189 Start ns_babysitter application as permanent too.

Hopefully it won't crash but it makes sense to terminate everything if
it does.

Change-Id: I635bbde856a519e7a3846d9ed53e96e6da179077
Reviewed-on: http://review.couchbase.org/26088
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>