validate list of emails. 🔐

Submit a list of emails and return the valid ones.<br/> Returns the not blacklisted emails of given list.<br/> If group_id is set, the active state is checked additionally.<br/> <br/> <strong>Example Post Data:</strong><br/> <code> {<br/>     "emails": [<br/>         "joker@arkham.com",<br/>         "twoface@dent.com",<br/>         "batman@gotham.com"<br/>     ],<br/>     "group_id": "1939",<br/>     "invert": false<br/> }<br/> </code>