RST files:

* Produce simple style guide and canonicalise usages to follow it
* Get rid of, or use proper Sphinx markup for, glossary

HTML Output:

* Styling for Cautions and Tips
* Stop replacement of "--" with em-dash
* Auto-highlighter thinks # in "bash#" is a comment char
* Style definition lists to have the term in bold
* Fix bug lifecycle image original doc link

Topics to cover:

* email_in.pl
