Full live (client side) validation, "developed" to use with simple_form
and foundation markup (should work in other cases too).
Create separate .coffee file e.g. client_side_select2.js.coffee
with following code:
# Add select2 support
ClientSideValidations.selectors.validate_inputs += ', select[data-select2-validate]'
ClientSideValidations.selectors.inputs += ', .select2-container'