Footer: show both "commit" and "last_updated" (if available)

Closes #238.

The alt attribute is only valid on the <area>, <img>, and <input>
elements, not <a>.

https://html.spec.whatwg.org/multipage/indices.html#attributes-3:attr-area-alt

This reverts commit 8f327360

 (#806).

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

Search page: don't show "edit on" links

Add a bottom margin for anything that does not match p, ul, ol

This is a compromise between the docutils intended style and more
consistent margins than 0.4.3.

0.5.0 was moving in the direction of treating everything like a simple
list. 0.4.3 had some bugs that made complex lists look closer to the
spacing that complex lists use. This resolves both and adds specific
item margins for both cases.

See https://docutils.sourceforge.io/sandbox/html4strict/data/simple-lists.html

All other elements should maybe have a bottom margin, but paragraphs and
nested lists should not have a bottom margin.

Fix a number of issues around margins on last children

The HTML4 writer depended on the `.last` selector, a class added by
Sphinx directly on output. Both writers are not using that method
anymore and instead relying on well supported CSS selectors.

This actually also addresses a number of inconsistencies with margin
spacing in lists. Version 0.4.3 and prior have a number of odd issues
around nested lists that are resolved with this change.

Also change the package lock file

This was missed and not picked up until after release.

Add colon after field list terms

Currently, python method parameter/etc field lists are the same class as
general field lists, so we can't treat them differently. This reverts
styling the field list without the colon for now, and is comparable to
how the HTML 4 writer outputs field/parameter lists.

This page is autogenerated, so it doesn't have "a real page".

Fixes https://github.com/readthedocs/sphinx_rtd_theme/issues/934

fix list style on nested lists

Change FOUT back to FOIT

The fonts loaded in 0.4.3 did not have a configuration for the CSS
`font-display`, and they were switched to `font-display: swap` in
0.5.0rc1. The old behavior was FOIT, and `swap` changed the behavior to
FOUT, which was more noticeable. This changes back to a long block
period while the fonts are loading.

For more information on the FOUT/FOIT and the font-display mechanism:
https://developer.mozilla.org/en-US/docs/Web/CSS/@font-face/font-display

Address issue with dl.simple definition lists

This was not a test case in our demo docs, and I'm still not entirely
sure why the style needs to be different. 🤷

Fixes #913

Release 0.5.0rc1

This is a release candidate for 0.5.0, which adds support for both HTML4
and HTML5 writers, which should support the default writer regardless of
your version of Sphinx.

Also included in this release are localization efforts and 10 language
translations.

You will need to specify the release manually to test, if there are no
major issues, we will have a 0.5.0 release shortly.

Closes #886
Closes #712

Use bumpversion for version number management