DokuWiki writer:  Use pointy brackets for email links.

(#1398)
DokuWiki writer:  More tweaks to email links. (#1398)
DokuWiki writer:  Updated tests.
DokuWiki writer:  Normalize to collapse adjacent raw HTML blocks.
DokuWiki writer:  Use raw HTML for complex lists...

as in the mediawiki writer.  The dokuwiki markup isn't able
to handle multiple block-level items within a list item, except
in a few special cases (e.g. code blocks, and these must be started
on the same line as the preceding paragraph).  So we fall back to
raw HTML for these.

Perhaps there is a better solution.  We can "fake" multiple
paragraphs within list items using hard line breaks (`\\`), but
we must keep everything on one line.

(#1398)