A long time ago, we added a new shortcode `codenew` as a replacement of
the `code` shortcode. The intention was to consolidate all example
manifests to a single subdirectory, i.e. `content/<lang>/examples`. Now
this transition is almost over. We have only two instances where the old
`code` shortcode is referenced.
This PR makes the `policy.rego` file inlined content so that all
referenes to `code` are killed. We can safely drop the `code` shortcode.
If desired, we can rename the `codenew` shortcode to `code` in a
(series of) separate PR(s).
This commit adds two backwards compatible changes to prepare for the next Hugo version, most notable:
* All the `File` methods on `Page` has been deprecated and will give a warning in the next Hugo version. Adjust this by changing `.Dir` to ´.File.Dir` and similar.
* Version the capture shortcode to use the old behaviour for markdown rendering of shortcode inner content.