Apparently style sheets can be used to control frames.

  Frame-based layout via Style Sheets (June 1996)
  http://www.w3.org/TR/NOTE-layout

This old note is an extension to CSS1 and seems to cover frames
unrelated to framesets currently used in the API docs generated by Javadoc.

We should modify the style sheet to set the width (and number?)
of the left-hand frames.

NOTE: Control may already be in the style sheet -- need to research
whether any generated files need to be changed to make this happen.