<system-data-structure>
   <asset type="file" identifier="icon" label="Image/Icon that will be a link to the Email-Friend Form" required="true" />
   <asset type="page" identifier="formPage" label="Page, with a form" required="true"/>
   <text identifier="fromEmail" label="Email address from which the emails will be sent" required="true"/>
   <asset type="file" identifier="script" label="PHP script that will send the email" required="true"/>
   <text identifier="contents" label="Default content of the email (will show on the form as default value)" multi-line="true" default="Hi, please take a look at this link."/>
</system-data-structure>
