Blogspot normalization edge-case issues

[jage]

• http://blogspot.com/ isn't normalized to http://www.blogspot.com/.
• http://www.blogspot.com/ is normalized to http://blogspot.com/ which it shouldn't do.

Diff:

$ git diff
diff --git a/spec/lib/twingly/url_spec.rb b/spec/lib/twingly/url_spec.rb
index 85c2903..d64efa8 100644
--- a/spec/lib/twingly/url_spec.rb
+++ b/spec/lib/twingly/url_spec.rb
@@ -197,6 +197,20 @@ describe Twingly::URL do
       it { is_expected.to eq(expected) }
     end

+    context "adds www if host is missing a subdomain" do
+      let(:url)      { "http://blogspot.com/" }
+      let(:expected) { "http://www.blogspot.com/" }
+
+      it { is_expected.to eq(expected) }
+    end
+
+    context "keeps www if host is missing a subdomain" do
+      let(:url)      { "http://www.blogspot.com/" }
+      let(:expected) { "http://www.blogspot.com/" }
+
+      it { is_expected.to eq(expected) }
+    end
+
     context "does not add www if the host has a subdomain" do
       let(:url) { "http://blog.twingly.com/" }