Exclamation points may be improperly encoded as image tags

[cultpony]

Hi,

I've encountered this running a few test comparing against the Elixir textile rendering, the following encoding seems to be a bit weird;

A! B! C.

renders to

<p>A<img src=" B"> C.</p>

while the proper result would be

<p>A! B! C.</p>

I'm bypassing it by encoding exclamation marks with trailing spaces but I don't think those should be images, as the source path isn't a valid URI to begin with.