Z-cart

-Updated to identify returning customers by Phone # and Email only. (all DB info is updated for customer on positive match).
-Added limits to all input fields so that SQL limits can not be exceeded.
-Added regular expression (RegEx) pattern requirements for zip code, phone number, and email fields.
-Added redirects in all PHP includes to redirect browsers to store front if they attempt to access a script.
-Added return address (auto populated from store_settings.php) to shipping labels
-Added RegEx requirements for stock and price in admin/maintenance.
-Menu is collapsible (default state is expanded).
-Added logout menu item in admin.

Also fixed all PHP warning messages. This should be the final release.