JCBC-495: Quotes round variables to accommodate pathnames with spaces

Change-Id: I9dc381a1b7223c4ed3c23c14989e4261f50badba
Reviewed-on: http://review.couchbase.org/39443
Reviewed-by: Matt Ingenthron <matt@couchbase.com>
Reviewed-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>