Support embedded HTML

[xcatliu]

Does this support embedded HTML like this:

[Hello](test)

<a href="test2">Hello2</a>

to:

<p><a href="http://me.com/test">Hello</a></p>

<a href="http://me.com/test2">Hello2</a>

[xcatliu]

It seems that this can be achieved in this way: https://github.com/nasa8x/markdown-it-redirect/blob/master/src/index.js#L15

[Martin Heidegger]

Added support for html tags in 1.2.0