Update content variable references in containers

[wezell]

When adding variables to a container, our javascript uses old variable references for the content properties. We need to change this to use the $dotContentMap to reference the variables. So, instead of adding $title we need to add $dotContentMap.title.

https://user-images.githubusercontent.com/934364/190672313-8802c053-79f8-455a-8d84-8000028c169d.mov