Inconsistent tracking of checked attribute on input element

[craigballinger]

It appears that the first user interaction with the checkbox input element in the browser triggers an "on" state in the DOM/object property regardless of the value/v-model of the toggle button.

In many use cases, it's probably irrelevant in a practical sense, but when using the toggle in a form that is actually submitted it can become problematic.

Adding :checked="value" seems to resolve the issue. PR submitted. Thanks!

[euvl]

Well done, merged