It contains all the menu entries so you can customize it to fit your needs. But, please, be aware that you'll need to rewrite your changes after every fab-manager's updates.
For a short explanation,
state links to an angular router state, as defined in router.coffee.erb,
linkText refers to an i18n constant, defined in app.public.LOCALE.yml and
linkIcon refers to the name of a font-awesome icon.