Redesign HTML parsing.

Most importantly, take into account elements that have implicit close
tags. For example in this HTML:

    <ul><li>0</li><li>1<li>2</ul>

The first <li> is closed with an explicit </li>, the second <li> is
closed by another <li>, and the third <li> is closed by the end of the
parent </ul>.

Note that this isn't really attempting "pragmatic" parsing as does the
html-parsing package, because these rules are in the HTML5 spec:

http://www.w3.org/html/wg/drafts/html/master/syntax.html#syntax-tag-omission

Doing this is important for performance, because our worst case scenario
remains -- searching to EOF for a closing tag, not finding it,
backtracking, and repeating.
Bump to v0.11
Improve block vs. inline element predicates.

- Explicit list of inline elements.
- Complete block and line lists.
Different syntax for parse tests.
Change check-parse to with-parser
Fix bug with $any-open-tag
Tweak comment
$pre $script $style specializations of plain-body

All should simply parse $anyChar until their close tag.
$block-element need not list specific parsers.

There's no real speed advantage, it's just noise.
Define and use $not-block-element
Say that html head body are "block" elements

Useful fudge for parsing HTML in markdown.
Define $html-document and use with redex-test

The redex tester is really only generating HTML (not markdown) so simply
parse with that, instead.
Remove unused require of html
Don't parse as markdown contents of block HTML. Fixes #70.
with-parser: Fix srcloc
Fix typos in comments
Ensure \r\n -> \n for parser.

I misread the docs for `#:mode 'text` -- that only works on Windows.

This was compounded by my not noticing that Emacs was doing \r\n -> \n
automatically when I would copy and paste fragments from a file with
\r\n, and those would of course work.
Use new `manyUntil` from Parsack.

Required for the `lookAhead` in `flexi` to work properly in all cases,
so that our optional closing tag logic actually works.
Convert <lj-cut> elements to <!-- more -->

Also tolerate badly formed HTML with lj-cut tags, by discarding the
close tag. We only care about the open tag position, anyway.
More unit tests.