[ticket/12733] Add Twitter custom profile field

PHPBB3-12733

phpBB/language/en/common.php

@@ -771,6 +771,7 @@ $lang = array_merge($lang, array(
 		2	=> 'Total members <strong>%d</strong>',
 	),
 	'TRACKED_PHP_ERROR'	=> 'Tracked PHP errors: %s',
+	'TWITTER'			=> 'Twitter',
 
 	'UNABLE_GET_IMAGE_SIZE'	=> 'It was not possible to determine the dimensions of the image. Please verify that the URL you entered is correct.',
 	'UNABLE_TO_DELIVER_FILE'=> 'Unable to deliver file.',

phpBB/language/en/memberlist.php

@@ -144,4 +144,5 @@ $lang = array_merge($lang, array(
 	'USERS_PER_PAGE'		=> 'Users per page',
 
 	'VIEWING_PROFILE'		=> 'Viewing profile - %s',
+	'VIEW_TWITTER_PROFILE'  => 'View Twitter Profile',
 ));