Fix broken link

All of docs.writethedocs.org gives access denied, but the content can be found at www.writethedocs.org
Someone with contacts at writethedocs.org should recommend they redirect docs to www in addition though; there's probably lots of other links out there.

docs/getting_started.rst

@@ -144,7 +144,7 @@ If you have any more trouble, don't hesitate to reach out to us. The :doc:`suppo
 .. _install Sphinx: http://sphinx-doc.org/latest/install.html
 .. _install Mkdocs: http://www.mkdocs.org/#installation
 .. _reStructuredText: http://sphinx-doc.org/rest.html
-.. _this template: http://docs.writethedocs.org/guide/writing/beginners-guide-to-docs/#id1
+.. _this template: http://www.writethedocs.org/guide/writing/beginners-guide-to-docs/#id1
 .. _Sign up: http://readthedocs.org/accounts/signup
 .. _log in: http://readthedocs.org/accounts/login
 .. _dashboard: http://readthedocs.org/dashboard