Rework form config array so that each field attr is an array with 'label', 'rules', 'messages'

[macder]

new structure should look like:

array(
  'email' => [
    'label' => 'Email',
    'rules' => 'required|email',
    'messages' => [
      'required' => 'Custom required validation error msg',
      'email'    => 'No email? No soup for you!',
    ],
   'phone' => [
      //...
   ]
  ]
);