Merge pull request #510 from MITx/kimth/blog-link-fix

Blog link fix

lms/templates/footer.html

@@ -9,7 +9,7 @@
         <a href="https://www.edx.org" class="logo"></a>
         <a href="${reverse('courses')}">Find Courses</a>
         <a href="${reverse('about_edx')}">About</a>
-        <a href="http://edxonline.tumblr.com/">Blog</a>
+        <a href="http://blog.edx.org/">Blog</a>
         <a href="${reverse('jobs')}">Jobs</a>
         <a href="${reverse('contact')}">Contact</a>
       </section>