Unlock default patterns

The user should be able to customize all patterns, including those that come with the module. Yet we must give third-party module developers the confidence that the patterns they use will be available.

To do that, we should allow per-field patterns. Something like this:

$form['ip'] = [
  '#type' => 'textfield',
  '#title' => t('IP address'),
  '#mask' => [
    'value' => '099.099.099.099',
    'reverse' => FALSE,
    'selectonfocus' => FALSE,
    'clearifnotmatch' => TRUE,
    'translation' => [
      '0' => [
        'pattern' => '\d',
      ],
      '9' => [
        'pattern' => '\d',
        'optional' => TRUE,
      ],
    ],
  ],
];

These settings would overwrite the module's global settings for that field.

However, having to write all these translation patterns every time is tedious. So we should provide some method to provide the translation patterns just once per module.