Adding -n switch to template for main varnish configuration file.
Previously, INSTANCE was defined, but not used, so instance was always
'default' (uname -n).
Checking the params file, the default value for $instance is 'default',
so adding a check to not change behaviour, if this instance name is
specified.
Varnish:
 Changing template logic for varnish conf file so that no change in
behaviour is made for installations that do no specify the instance
name.
Merge branch 'master' of https://github.com/malaikah/puppet-varnish into malaikah-master
Fix specs for new rspec version
Fix spec for changes on issue #7
Merge branch 'malaikah-master' (close #7)