Markdown Table Extension

Markdown pipe tables support a {width} spec on header cells to set column widths in generated HTML and PDF output:

| Name{120} | Description{*} | Status{50%} |
| --------- | -------------- | ----------- |
| foo       | bar            | active      |

Spec	Meaning	Example HTML
{N}	CSS width — bare numbers default to pixels	<col style="width:120px" ...>
{Npx}	Explicit pixels	<col style="width:120px" ...>
{N%}	Percentage of the table width	<col style="width:50%" ...>
{Nunit}	Any valid CSS unit (em, rem, vw, …)	<col style="width:10em">
{*}	Auto (no constraint)	<col />

The spec is stripped from the rendered header text and a <colgroup> of <col> elements is inserted into the <table>. Columns without a {width} spec are left unconstrained.