I hadn't made a proper release in a long time, so I thought it was better not to postpone anymore. Besides updating a few dependencies, 0.17.0 removes a few feature that were not really maintained anymore, such as a libreoffice writer export.

* Try to get rid of technical debt, including removing features that were half baked and not really useful.
  * Remove proofread options.
  * Remove ODT renderer.
  * Replace mustache for templates by [upon](https://crates.io/crates/upon)
  * Use rust-i18n for internationalization instead of hackish (and unmaintained) crowbook-intl
* HTML:
  * When hovering a mouse hover a footnote, display its content to the side of the page.
* LaTeX:
   * Add `tex.cover` option to embed the cover image in the PDF file