Revert "remove custom stuff temporarily"

This reverts commit 1b69de04eb.

book/_config.yml

@@ -14,13 +14,21 @@ html:
 
 sphinx:
   config:
+    html_js_files:
+    - https://cdnjs.cloudflare.com/ajax/libs/require.js/2.3.4/require.min.js
+    thebe_config:
+      use_thebe_lite: true
+      exclude_patterns: ["**/_*.yml", "**/*.md", "**/*.ipynb"]
     html_theme_options:
       repository_url: "https://github.com/TeachBooks/template" #add your own repo URL here
       use_repository_button: true
       use_issues_button : true
+      launch_buttons:
+        thebe: true
     html_show_copyright: false
   extra_extensions:
     - sphinx.ext.imgconverter
+    - jupyterbook_patches
 
 bibtex_bibfiles: 
   - references.bib