Tests the installation or uninstallation of a package.

• Tests all install actions, etc. and warns of any errors
• Requires a valid package filename in $_REQUEST['package']
• Requires the admin_forum permission
• Uses the Packages language and template
• Accessed at index.php?action=packages;sa=install;package={package_name} or index.php?action=packages;sa=uninstall;package={package_name}
• Handles various errors that could occur
• Deletes the Packages/temp directory and tries to recreate it
• Asks for FTP info if it's needed