Added bulma-block-list to extensions

docs/extensions.html

@@ -126,6 +126,9 @@ extensions:
 - name: bulma-dashboard
   url: https://github.com/lucperkins/bulma-dashboard
   slug: bulma-dashboard
+- name: bulma-block-list
+  url: https://github.com/chrisrhymes/bulma-block-list
+  slug: bulma-block-list
 ---
 
 {% for extension in page.extensions %}