is module and spec. Set up karma for unit test. DMPRoadmap/roadmap#601

Added constants, isValidInputType and debounce as ES6 modules. DMPRoadmap/roadmap#601

tinymce refactoring for notes using JS. DMPRoadmap/roadmap#571

tinymce refactoring for answers using JS. TODO adding events. DMPRoadmap/roadmap#571

tinymce gem removed from any view. DMPRoadmap/roadmap#571

tinymce answer events for editor working. DMPRoadmap/roadmap#571

fixed typos in js.erb template. DMPRoadmap/roadmap#571

extend renamed to define since more appropiate. DMPRoadmap/roadmap#571