A security check for xoops register and login by using visual confirmation.

This is a quick bug-fix and feature-add release. Acturally both v1.0 and v1.1 released on Eastern Time, 2004/09/16. However I would take the Beijing Time for the v1.1 release.

Change log:
1 It's glad to find the author of the wonderful image-creation scripts, Society, which was stated as "Dennis Paulisch" in v1.0.
He made the first plug-in for xoops register security check (Thanks Predator for providing the scripts).
The story can be found: http://www.xoops.org/modules/news/article.php?storyid=1715&com_id=9837&com_rootid=9837&#comment9837
2 Add login check to closed-site login.
3 Check if its associated code-file exists before returning a confirm id.

How to user it:
1 File Install
For login, overwrite your files with the folder 'securitycheck_for_login'
For register, overwrite your files with the folder 'securitycheck_for_register'
For both login and register, overwrite your files with the folder 'securitycheck'
2 Module update
If you install for login, once uploading the files, go to Administration Area and update the system module
3 Make it work
3.1 To enable the security check, go to xoopsroot/include/common.php
Set:
define('ENABLE_SECURITYCHECK_REGISTER', 1);
define('ENABLE_SECURITYCHECK_LOGIN', 1);
3.2 Set other parameters in xoopsroot/include/common.php
if(!defined('STORE_IN_DB')) define('STORE_IN_DB', 0);
if(!defined('SECURITYCHECK_TABLE')) define('SECURITYCHECK_TABLE', "security");
if(!defined('MAX_ATTEMPTS')) define('MAX_ATTEMPTS', 10);
3.3 If you set define('STORE_IN_DB', 1), you will need create a table !