Revert "no ad, for now"

This reverts commit ceffbd8.

Author: kennethreitz

docs/_templates/sidebarintro.html

@@ -22,9 +22,9 @@ <h3>Stay Informed</h3>
 <p><a href="https://saythanks.io/to/kennethreitz">Say Thanks!</a></p>
 
 
-<!-- <a href="http://www.datacamp.com/?utm_source=python_guide&utm_campaign=display">
+<a href="http://www.datacamp.com/?utm_source=python_guide&utm_campaign=display">
 <img src="{{ pathto('_static/ad.png', 1) }}" alt="">
-</a> -->
+</a>
 
 <hr>
 

docs/_templates/sidebarlogo.html

@@ -19,9 +19,9 @@ <h3>Get Updates</h3>
 <p><a href="https://saythanks.io/to/kennethreitz">Say Thanks!</a></p>
 <p><a href="http://tinyletter.com/kennethreitz">Join Mailing List</a>.</p>
 
-<!-- <a href="http://www.datacamp.com/?utm_source=python_guide&utm_campaign=display">
+<a href="http://www.datacamp.com/?utm_source=python_guide&utm_campaign=display">
 <img src="{{ pathto('_static/ad.png', 1) }}" alt="">
-</a> -->
+</a>
 
 <hr>