Issue #3493832: Allow custom data-options to added to elements JavaScript options

js/webform.element.choices.js

js/webform.element.chosen.js

js/webform.element.counter.js

js/webform.element.select2.js

js/webform.element.signature.js

js/webform.element.telephone.js

js/webform.element.time.js

...s/webform_image_select/js/webform_image_select.element.js

...ryui_datepicker/js/webform_jqueryui_datepicker.element.js

modules/webform_toggles/js/webform_toggles.element.js