[Docutils-develop] Renaming html4css1 to generic_html and supporting multiple dialects

[Armin R. <arm...@ac...>]

Hi all,

I've noticed that html4css1 doesn't output HTML4 but XHTML1.  Not only is this
misleading but also a bit problematic as XHTML is currently badly supported by
browsers.  All of the new websites I create are based on HTML4 again as it
causes much less trouble and it's easier to create valid pages that also render
well on current browsers.  Additionally HTML5 will probably attract some more
web developers in the future which brings me to the following proposal:

- rename html4css1 to generic_html
- add a "dialect" parameter to the write that can be set to one of the
  following values: html4, xhtml1, html5
- set default to xhtml1 for backwards compatibility

The writer is currently generating mostly HTML4 compatible code anyways so
switching between those dialects shouldn't be that hard.  It mostly affects
CDATA sections (currently just inline stylesheets as far as i can see),
Null-End-Tags and the doctype.

I'm willed to implement that and provide a patch.

Regards,
Armin