some language additions and tiny bugfixes related to the request_var change

git-svn-id: file:///svn/phpbb/trunk@5156 89ea8834-ac86-4346-8a33-228a782c2dd0

phpBB/language/en/groups.php

@@ -45,6 +45,8 @@ $lang += array(
 	'GROUP_IS_FREE'		=> 'This is a freely open group, all new members are welcome.', 
 	'GROUP_IS_SPECIAL'	=> 'This is a special group, special groups are managed by the board administrators.', 
 
+	'LOGIN_EXPLAIN_GROUP'	=> 'You need to login to view group details',
+	
 	'REMOVE_SELECTED'	=> 'Remove selected',
 );