This adds a line to show the camera model and make, if available, and
reorders and cleans up the EXIF parameters extracted so they are more
readable for photographers (who are the ones who care about this
anyways).

Note that, as a photographer, I know what "Fstop" mean, but I would
expect "exposure" or the common f/X.Y notation. The "Focal" label
means nothing to me: "Focal length" would mean something, but it's
long - and what are the units? Just using "mm" here clarifies any
possible misunderstanding.

I have found this format to be way more readable. The following:

    ISO: 3200, Focal: 50, Exposure: 1/40, Fstop: 4.0
    Date: dimanche, 31. décembre 2017

Becomes:

    ISO 3200, 1/40s f/4.0, 50mm
    FUJIFILM X-T2
    dimanche, 31. décembre 2017

Now: dropping the explicit labels may be controversial, but I would
argue this is what markup is for. We could wrap those elements in
named <span> or <acronym> elements to provide more information through
mouse-over or CSS.

Keep the normal font for browsers that switch to smallcaps, as
suggested by MDN:

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/abbr

We remove the dotted line normalization currently configured in the
`normalize.css` file because it actually creates a *second* dotted
line in Firefox 57. The directive there is `text-decoration` which is
what we disable here instead. It looks better without any dotted line.

We leave the trailing commas and strings like `ISO`, `f/` or `mm` but
those could also be managed through CSS. `<br>` tags may similarly be
managed better through CSS as well.

This way our changes will survive eventual normalize.css updates.

This way this can be override by client-side CSS or more easily controled through the theme