Add Google reCaptcha 2 validator

[simivar]

New Google reCaptcha 2 validator.

Google reCaptcha API CAN NOT be included by hand. Script handles that for user. reCaptcha validator works on hidden input even when validateHiddenInputs is set to false.

Example of usage:

<input type="hidden" data-validation="recaptcha" />
...
<script>
$.validate({
     modules: 'security',
     reCaptchaSiteKey: 'yourSiteKey', // required
     reCaptchaTheme: 'light' // light|dark, default: light
});
</script>

Or:

<input type="hidden" 
   data-validation="recaptcha" 
   data-validation-recaptcha-sitekey="yourSiteKey" 
   data-validation-recaptcha-theme="light" />

[victorjonsson]

This is a truly great feature!

[victorjonsson]

Use $.fn.valAttr instead of $.fn.data

[victorjonsson]

Great contribution! The plugin was lacking a solid captcha solution.