Update padrino admin pages
Major refactoring: rename Characteristic to TagField
Regenerate whole padrino admin
Order tags by level in tag fields
Add forgotten files related to last major refactoring
Implement basic level definitions for tag fields, with inline editing
Add 'tops' on homepage
Make first colum wider for people and projects
Better title for tag list title
Rename Characteristic to TagField in specs

* TODO: make sure all specs pass, fix broken ones