Custom BBCode to display Gists from Github

gist_bbcode.textile

BBCode usage:

[gist={IDENTIFIER}]{TEXT}[/gist]

HTML replacement:

<div class="github-gist">
  <span class="github-gist-headline">
    <img src="https://a248.e.akamai.net/assets.github.com/images/gravatars/gravatar-140.png" class="avatar" />
    <a href="https://gist.github.com/{IDENTIFIER}">gist: {IDENTIFIER}</a> :
      {TEXT}
  </span>
  <br />