Switched to using contain

This is intended to fix a problem where setting a require on the class
declaration like below doesn't actually work.

class {'::autosign':
  ensure  => present,
  require => Package['gcc'],
}

Being able to do a require like this is needed so that GCC is installed
prior to the autosign gem.

manifests/init.pp

@@ -27,7 +27,9 @@
   validate_string($package_name)
   validate_string($ensure)
 
-  class { '::autosign::install': } ->
-  class { '::autosign::config': } ~>
-  Class['::autosign']
+  contain ::autosign::install
+  contain ::autosign::config
+
+  Class['::autosign::install']
+  -> Class['::autosign::config']
 }