* add *.jinja templates (for the email templates) to the MANIFEST.in

* have the browser open the legal documents in a new tab
* link to the english version of forschungsdaten.at
* move the invenio_theme_tuw templates into the semantic-ui directory
* add flask extension for the module that instantiates the blueprint and
  moves it to the front of app._blueprint_order, such that it is
  encountered before the blueprints from invenio-app-rdm during
  render_template
* this enables us to place the template overrides in theme-tuw instead
  the git repository for tu data