Refs #17713 - WIP - Add document completion logic
Refs #17713 - WIP - Add control panel views and edits
Refs #17713 - Implement edit form for progressbar widgets
Refs #17713 - WIP - document completion viewlet
Refs #17713 - Test horizontal scroll within metadata viewlet
Refs #17713 - Fix horizontal scroll steps and CSS
Refs #17713 - Add depenedency to eea.jquery: serialscroll
Refs #17713 - Add document completion portlet

- Add portlet;
- Update documentation;
- Update and fix CSS and JS;
- Update version to 3.0;
Refs #17713 - Enhance next/prev buttons within editing progress viewlet
Refs #17713 - Add upgrade step to HISTORY
[JENKINS] - Fix tests
[JENKINS] - Fix plone4 demo buildout