Sends basic stats off to SimpleMachines.org if enabled.

• Information sent: UID (unique ID), time (used to indicate when these stats were added), total members, total posts, total topics, boards (currently just set at 0), PHP version, MySQL version, forum version and forum database version.
• Can be disabled by running upgrade.php and unchecking the appropriate box or by clearing out the value for "allow_sm_stats" in the settings table
• Does not work if fsockopen, fwrite or fclose are disabled
• See http://www.simplemachines.org/about/stats.php for more info