Heroku buildpack: MultiMarkdown

Run a static web site from MultiMarkdown files bult using MultiMarkdown-4.

Create an index.md file:
```
 echo "# hello, world" > index.md
```

Create a git repo containing the file:

 git init
 git add index.md
 git commit -m init

Create an app on Heroku:

 heroku create -s cedar-14 --buildpack https://github.com/npalmius/heroku-buildpack-multimarkdown.git

Push the repo to Heroku:
```
 git push heroku master
```
Open your web app:
```
 heroku open
```