Add new meta tags: pragma, cache-control, expires

Any news on this?
Thanks!

Needs some further work, inc outputting the tag as a http-equiv tag instead of a regular meta tag, which may involve some API changes.

Thanks for the update Damien!

New version of patch which works with latest dev version

@friera: Thanks. As a reminder, please change the status to "Needs review" after you upload a patch, that'll trigger the automated tests and helps people identify issues that need review rather than code work. That said, a few extra fields need to be added to metatag_metatag_info, e.g. 'weight'.

The patch needs to be rerolled.

Updated.

Committed.