tree 1c1a63a2027eb3182fe9d318c481807fe4f80cc2
parent b304a0585110b38cd9043dea950b070a0ea4d01e
author Shawn Pearce <sop@google.com> 1423807848 -0800
committer Shawn Pearce <sop@google.com> 1423807848 -0800

Markdown: accept GitHub style -- for <hr>

GitHub flavor markdown apparently accepts -- surrounded by
blank lines as an <hr> in HTML:

  Blah blah lots of text.

  --

  More text after the rule.

Support this by adding a custom rule to the parser that
recognizes this style and creates a HRule node.

Change-Id: I406e6d9def04ff2e3589a72316c28b3ddc773cd0