Address Firefox table-rendering issues in docs. Refactor to use colspan to provide table cells which can vary in width and indentation; the outermost has the greatest colspan, and each nested key has a colspan of one less than the parent, with padding cells for indentation.
Apply styling to table cells to get the table height to work without hacks or browser-specific
styling. Simplify the markup and CSS by removing extra divs. Use two passes over the options, return values, and return facts in the Jinja2 module-docs template: one to determine the maximum nesting depth to compute the maximum colspan needed, plus one to lay out the rows.
(cherry picked from commit fa5c0282a4)
7d3ce99a6f