Update _config.yml

Author: davidlange6

_config.yml

@@ -38,7 +38,7 @@ kramdown:
   auto_ids: true
   footnote_nr: 1
   entity_output: as_char
-  toc_levels: 1..1
+  toc_levels: 1..2
   smart_quotes: lsquo,rsquo,ldquo,rdquo
   enable_coderay: false
   parse_block_html: true # default for kramdown is false. This will enable using Markdown links