CBQE-0: allow pass char "'" in conf files

Change-Id: If0bf9ee4d88974630068268c2bfb1a9bf229bed0
Reviewed-on: http://review.couchbase.org/27294
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>