Project: sass
Task (moderate): Class RatingQuestion (file 'common/RatingQuestion.js', 'common/RatingQuestion.scss') inherits from Question. Its constructor params are: title (string), name (string), preview (boolean), starCount (number, default 5). Add a button (class 'add-rating') in 'common/SurveyDesign.js', and click it to create a RatingQuestion (random title, unique name) whose root is prepended to the form. Add a config panel checkbox (class 'q-starCount') associated with 'RatingQuestion.starCount'. Highlight star options (class 'option') up to the clicked star option, and get the rating value (stored in param-named control) from 0 to 1.