API Doc Improvements

This commit incorporates several sylistic changes aimed at improving the readability of the API documentation for Chicago Boss.

Visually, the biggest change is that a command and its explaination appear on the same line. This has been implemented with tables.

## Changes (enhancements, hopefully)

  * CSS
  * converted `<div class="code spec">` and `<p>` pairs to rows of tables
  * added several `&nbsp;` to minimise tables collapsing in the wrong place
  * removed references to maps.evanmiller.org in CSS, which were resulting in 404 errors