Fix formatting of group_default sliders and stars.
	modified:   app/helpers/surveyform_helper.rb - check for group_default
	and add a class "default" to distinguish from grid and inline.

	modified:   app/views/surveyforms/_question_field.html.erb - add a wrapper
	div around slider.

	modified:   lib/assets/stylesheets/surveyor_gui/surveyor_gui.sass