Added review slides to index to remove toctree warning.
Added review slides to index to remove toctree warning.

13_review wasn't in the list so I added it. No more warnings!

edunham/website,DevOpsBootcamp/website,edunham/website,edunham/website,DevOpsBootcamp/website,reillysiemens/curriculum,edunham/website,DevOpsBootcamp/website,reillysiemens/curriculum,reillysiemens/curriculum