Documentation page for Partials seems to be out of date

[Mims H. Wright]

Comparing the live docs:
http://assemble.io/docs/Partials.html

To what's in the reop:
https://github.com/assemble/assemble.io/blob/master/templates/pages/docs/Partials.md.hbs

Shows that there's a lot of content missing from the page.