Remove backend class

The backend class has been removed and the related
backend config service has been coupled with the
file and swift classes. This is to reduce the code
complexity.

manifests/backend.pp

@@ -1,15 +0,0 @@
-#
-# used to model the line in the file
-# that configures which storage backend
-# to use
-#
-class glance::backend(
-  $default_store
-) {
-  glance::api::config { 'backend':
-    config => {
-      'default_store' => $default_store
-    },
-    order  => '02',
-  }
-}

manifests/backend/file.pp

@@ -8,9 +8,15 @@ class glance::backend::file(
   $filesystem_store_datadir = '/var/lib/glance/images/'
 ) inherits glance::api {
 
-  # set file as default store
-  class { 'glance::backend':
-    default_store => 'file',
+  #
+  # modeled as its own config define so that any attempts to
+  # define multiple backends will fail
+  #
+  glance::api::config { 'backend':
+    config => {
+      'default_store' => 'file',
+    },
+    order  => '04',
   }
 
   # configure directory where files should be stored

manifests/backend/swift.pp

@@ -19,9 +19,15 @@ class glance::backend::swift(
   $swift_store_create_container_on_put = 'False',
 ) inherits glance::api {
 
-  # specify swift as backend
-  class { 'glance::backend':
-    default_store => 'swift',
+  #
+  # modeled as its own config define so that any attempts to
+  # define multiple backends will fail
+  #
+  glance::api::config { 'backend':
+    config => {
+      'default_store' => 'swift',
+    },
+    order  => '04',
   }
 
   glance::api::config { 'swift':

manifests/notify.pp

@@ -6,6 +6,7 @@
 class glance::notify(
   $notifier_strategy
 ) {
+
   glance::api::config { 'notify':
     config => {
       'notifier_strategy' => $notifier_strategy,