Custom Field theme function

custom_field.module

/**
 * Implements hook_theme().
 */
function custom_field_theme() {
  return array(
    'custom_field' => array(
      'template' => 'templates/custom-field',
      'variables' => array(
        'name' => NULL, 
        'content' => NULL, 
        'title' => NULL, 
        'title_wrapper' => 'h4',
        'title_classes' => array('field-label'), 
        'title_hidden' => FALSE,
        'container' => FALSE,
      ),
    ),
  );
}