Adds type field to release model.

spec/models/release_group_spec.rb

@@ -60,6 +60,7 @@ describe MusicBrainz::ReleaseGroup do
       releases.first.title.should == "Empire"
       releases.first.date.should == Date.new(2006, 8, 28)
       releases.first.country.should == "GB"
+      releases.first.type.should == "Album"
     end
   end
 end

spec/models/release_spec.rb

@@ -24,6 +24,7 @@ describe MusicBrainz::Release do
     release.asin.should == 'B002NOYX6I'
     release.barcode.should == '602527197692'
     release.quality.should == 'normal'
+    release.type.should == 'Album'
   end
 
   it "gets correct release tracks" do