Eliminating unneeded blank space character from show_date_tag

The space character causes the 'Show in x period' background color to
run into the todo description.

Closes #1368

app/helpers/todos_helper.rb

@@ -188,7 +188,7 @@ def staleness_class(item)
 
   def show_date_tag(date, the_class, text)
     content_tag(:a, :title => format_date(date)) do
-      content_tag(:span, :class => the_class) { text + " "}
+      content_tag(:span, :class => the_class) { text }
     end
   end