Added an advanced editor of fields for the Order Form.

Added an advanced editor of fields for the Order Form. You can create up to 50 fields, with different data types (text fields, strings, sending files, chachkbox and select elements). Form management is located in the settings, in the "Shop", "Checkout" tab.

Added option to separate address fields in the checkout form.
Added search and change of "Manufacturers" to the group editor.
Added the ability to specify an additional SMTP server for sending via the Database of e-mail addresses.