Fixes

• Update of price in WooCommerce does not update _EventCost
• Add attendee meta info to tickets email
• Ensure continued compatibility with WooCommerce
• Ensure continued compatibility with WP E-Commerce
• Made sure a SKU will be automatically generated for WooCommerce tickets if not provided.
• Resolve issue where "Don't list me on attendees public attendees list" is visible even when "Hide attendees list" is checked in admin