Fixed some installation issues:

- 'Missing Zone Folder' error was cleaned up
- Admin Hide Email Address itn't passed back (or maybe just display, could be the view) when you click 'Go Back' on the 'Confirm Admin Info' page (not when you're redirected because of errors)
- Added 'AllianceCMS: API' default link to 'Install/schemata/install_alpha.php'