In 0.3.0 of the json-exporter[1] it was switched to a different jsonpath
library which made some changes - especially for spaces in keys -
necessary. Also I decided to remove the pretty-printed JSON as this
would interfere with the bash quoting too much. If one needs
pretty-printed output, they can still pipe the output to `jq`.
[1] https://github.com/prometheus-community/json_exporter/releases/tag/v0.3.0
* Content of `programlisting` shouldn't be indented, otherwise it's
weirdly indented in the output.
* Use `<xref linkend=.../>` in the release notes: then users can
directly go to the option documentation when reading release notes.
* Don't use docbook tags in `mkRemovedOptionModule`: it's only used
during evaluation where docbook isn't rendered.
