[aws|compute] add tagSet to describe format

lib/fog/aws/requests/compute/create_volume.rb

@@ -47,6 +47,7 @@ module Fog
               'size'              => size,
               'snapshotId'        => snapshot_id,
               'status'            => 'creating',
+              'tagSet'            => {},
               'volumeId'          => volume_id
             }
             @data[:volumes][volume_id] = data

tests/aws/requests/compute/volume_tests.rb

@@ -21,13 +21,14 @@ Shindo.tests('AWS::Compute | volume requests', ['aws']) do
 
   @volumes_format = {
     'volumeSet' => [{
-      'availabilityZone'    => String,
-      'attachmentSet'       => [],
-      'createTime'          => Time,
-      'size'                => Integer,
-      'snapshotId'          => NilClass,
-      'status'              => String,
-      'volumeId'            => String
+      'availabilityZone'  => String,
+      'attachmentSet'     => [],
+      'createTime'        => Time,
+      'size'              => Integer,
+      'snapshotId'        => NilClass,
+      'status'            => String,
+      'tagSet'            => {},
+      'volumeId'          => String
     }],
     'requestId' => String
   }