CSS classes used to decorate `self`

Mainly used for icons.

Property definitions

	# CSS classes used to decorate `self`
	#
	# Mainly used for icons.
	var css_classes: Array[String] = collect_modifiers is lazy

src/doc/templates/html_model.nit:92,2--95,59

	redef var css_classes = ["public"]

src/doc/templates/html_model.nit:101,2--35