Usage of dangling ] messes up the parser.

STR:

* Use ]] in your string.
* Observe the markdown output.

Expected:

* ]] should come up normally.

Actual:

* ]] doesn't come up.

[Demo](http://jsfiddle.net/onzm2vyc/21/). Compare it with [remarkable](https://jonschlinkert.github.io/remarkable/demo/)

Why I care ?

A Punjabi font uses roman characters to form Punjabi alphabets. It uses ]] for what is know as full stop in Punjabi. It is broken now after I moved from remarkable to snarkdown. I love the perf and size of library, and I understand why this might not be considered to be fixed, but I thought it's worth the shot!