remove leading and trailing underscores from title_as_url

app/models/story.rb

@@ -180,7 +180,7 @@ class Story < ActiveRecord::Base
     while u.match(/__/)
       u.gsub!("__", "_")
     end
-    u
+    u.gsub(/^_+/, "").gsub(/_+$/, "")
   end
 
   def url_or_comments_url(root_url = "/")

spec/models/story_spec.rb

@@ -93,4 +93,9 @@ describe Story do
       "spec/fixtures/story_pages/2.html")
     s.fetched_title.should == "Google"
   end
+
+  it "has an underscored url from its title" do
+    s = Story.make(:title => "The One-second War (What Time Will You Die?) ")
+    s.title_as_url.should == "the_one-second_war_what_time_will_you_die"
+  end
 end