typographical quotes not always replaced about lowdown

[kristapsdz]

Good catch! Can you confirm that the above commit (which includes a regression test) fixes your issue and any similar ones you've found? If so, I'll roll into the next release in a day or so.

[step-]

Yes, I can confirm that the fix is good, thank you!
I happened on this bug while comparing some markdown converters to each other. As you can well imagine, each program takes a different (not necessarily wrong) stance on smart quotes. Here's an example.

                                          other
<p>A“<br/>
B” “C<br/>
”D</p>
                                          /tmp/lowdown/lowdown
<p>A&#8221;<br/>
B&#8221;
&#8220;C<br/>
&#8220;D</p>
                                          pandoc
<p>A”<br />
B” “C<br />
”D</p>