Please add event on rgba-color-picker change

[danyj]

In default color picker we have this event

                $input.trigger('fw:color:picker:changed', {
                    $element: $input,
                    event   : event,
                    ui      : ui
                });

https://github.com/ThemeFuse/Unyson/blob/master/framework/includes/option-types/color-picker/static/js/scripts.js#L42

it is missing here

https://github.com/ThemeFuse/Unyson/blob/master/framework/includes/option-types/rgba-color-picker/static/js/scripts.js#L52

and here

https://github.com/ThemeFuse/Unyson/blob/master/framework/includes/option-types/rgba-color-picker/static/js/scripts.js#L105

Please add it in so that we can track the color changes. Thank you!