WL-3608 : The site contact should always be given in the drop down list of "recipient"

1.   I've removed showing the Site Contact as a label on the forms.
2.   In FeedbackTool, I'm adding the Site Contact to the list of siteUpdaters. The problem is that the list of siteUpdaters has the userId as the value of each option in dropdown whereas the site contact doesn't have to be a user.  So I'm putting the email address in there instead and testing to see if it's a valid email address the other side in FeedbackEntityProvider.