Preformatted text

[ehrencrona]

Maintain whitespace and newlines as-in inside <pre> tags, i.e. formatting

<pre>
  _______
 /  12   \
|    |    |
|9   |   3|
|     \   |
|         |
 \___6___/
</pre>

does not turn into

<pre> _______ / 12 \\ | | | |9 | 3| | \\ | | | \\___6___/</pre>

Also consider attribute values (with one exception: the class attribute) to be pre-formatted. Do not add or remove line breaks there.

This builds on PR #120. I thought it sensible to nevertheless keep it as a separate PR.

I got some code from #41, e.g. the isPreTagContent function.

Relates to #28 . I chose not to pursue the idea of configuring which tags are white-space sensitive. I'm happy to add that if there is a feeling it should be added; in any case it can easily be added on top of this PR.

[dummdidumm]

I'm a little confused now on what to review first 😄 does this PR contain everything of #120 + the additional <pre> behavior?

[ehrencrona]

@dummdidumm Yes it does. It probably makes sense to first review #120. If that is ok, this one (#127) can be reviewed and #116 can be closed.

If #120 is rejected, #127 can be closed (because it builds on it) but it's still worth taking a look at #116.

[dummdidumm]

One minor suggestion, that's all. 👍