feat(ngmodelctrl_parse_format): time fields example and date field exercise

@IgorMinar another demo + exercise, this time illustrating integration with parsers / formatters infrastructure of the NgModelController. 

Would be great to have your opinion on 2 proposed way of plugging parsers and formatters (see https://github.com/pkozlowski-opensource/directives-workshop/blob/ngmodelctrl_parse_format/src/ngmodelctrl_parse_format/demo/timefields.js ). While both work tests are quite different (DOM based vs. JS functions testing).