clarify page sorting test

test/test_site.rb

@@ -154,9 +154,7 @@ def generate(site)
       assert_equal @site.generators.sort_by(&:class).map{|g|g.class.priority}, @site.generators.map{|g|g.class.priority}
     end
 
-    should "sort pages in a consistent way" do
-      # The order that files are returned differs across operating systems, so ensure that they're being sorted after the fact.
-      # http://stackoverflow.com/a/5529966/358804
+    should "sort pages alphabetically" do
       stub.proxy(Dir).entries { |entries| entries.reverse }
       @site.process
       sorted_pages = %w(.htaccess about.html bar.html contacts.html deal.with.dots.html foo.md index.html index.html sitemap.xml symlinked-file)