remove folders:true and add toc back into frontmatter

Author: poldrack

book/frontmatter.md

@@ -13,6 +13,10 @@ The book is licensed according to the [Creative Commons Attribution-NonCommercia
 
 See table of contents in the sidebar to the left.
 
+```
+{tableofcontents}
+```
+
 ### Acknowledgements
 
 I'd like to acknowledge the following individuals for their helpful comments/suggestions/pull requests on the book:  [Giorgio Arcara](https://github.com/giorgioarcara), [Steffen Bollman](https://github.com/stebo85), [Joshua Buckholtz](https://github.com/jwbuckholtz), [Satchel Grant](https://github.com/grantsrb/), [Yaroslav Halchenko](https://github.com/yarikoptic), [Chris Markiewicz](https://github.com/effigies) and [Jeanette Mumford](https://github.com/jmumford).

myst.yml

@@ -30,5 +30,5 @@ project:
 site:
   options:
     logo: logo.png
-    folders: true
+#    folders: true
   template: book-theme