add intro to toc (#187) (#195)

* add intro to toc

* fix error

(cherry picked from commit 7e45d02)

# Conflicts:
#	source/includes/steps-ak8so-helm-quick-start.yaml

Author: jwilliams-mongo

source/index.txt

@@ -198,6 +198,7 @@ Get Hands-On Experience with |ak8so|
 .. toctree::
    :titlesonly:
 
+   Overview </index>
    Get Started </ak8so-get-started>
    Atlas Access </configure-ak8so-access-to-atlas>
    Import Projects </ak8so-import-projects>