Allow changing the location of subscribe/unsubcribe pages

I needed to change where the opt-in and opt-out pages were located so I modified the module with the following changes:

mailchimp.admin.inc.php (line 25)

  $form['mailchimp_page_info'] = array(
  	'#type' 		=> 'fieldset',
	'#title'		=> 'MailChimp Opt-in/Opt-out Pages',
	'#description'	=> 'Use these options to change the MailChimp user page locations.',
	'#collapsible'	=> TRUE,
	'#collapsed'	=> TRUE,
	'mailchimp_opt_in_page_path' => array(
		'#type'			=> 'textfield',
		'#title'		=> t('MailChimp Opt-in Page'),
		'#description'	=> t('Enter a drupal path for the MailChimp Opt-in page.<br/>Note: if you change the default you will have to flush the menu cache for the change to take effect.<br/>Default: mailchimp/subscribe'),
		'#default_value'=> variable_get('mailchimp_opt_in_page_path','mailchimp/subscribe'),
	),
	'mailchimp_opt_out_page_path' => array(
		'#type'			=> 'textfield',
		'#title'		=> t('MailChimp Opt-out Page'),
		'#description'	=> t('Enter a drupal path for the MailChimp Opt-out page.<br/>Note: if you change the default you will have to flush the menu cache for the change to take effect.<br/>Default: mailchimp/unsubscribe'),
		'#default_value'=> variable_get('mailchimp_opt_out_page_path','mailchimp/unsubscribe'),
	),
  );

After adding that, the links in the admin form to those pages need to be updated as well.

mailchimp.admin.inc.php (line 175)

'#description'    => t('The page title to display on the !subscribe_page.', array('!subscribe_page' => l(t('Subscribe page'), variable_get('mailchimp_opt_in_page_path','mailchimp/subscribe')))),

mailchimp.admin.inc.php (line 182)

'#description'    => t('The page title to display on the !unsubscribe_page.', array('!unsubscribe_page' => l(t('Unsubscribe page'), variable_get('mailchimp_opt_out_page_path','mailchimp/unsubscribe')))),

mailchimp.admin.inc.php (line 189)

'#description'    => t('The text to display above the form on the !unsubscribe_page.', array('!unsubscribe_page' => l(t('Unsubscribe page'), variable_get('mailchimp_opt_out_page_path','mailchimp/unsubscribe')))),

Then change the links in the mailchimp_menu function to use the new option.

mailchimp.module (line 405)

$items[variable_get('mailchimp_opt_in_page_path','mailchimp/subscribe')] = array(

mailchimp.module (line 411)

$items[variable_get('mailchimp_opt_out_page_path','mailchimp/unsubscribe')] = array(