Made sure that empty e-mail fields are not shown when sending newslet…

…ters. (An empty e-mail field comes when a user has had an e-mail adress but it was removed, thus it is not NULL but an empty string. Maybe this should be changed?)

app/models/email.rb

@@ -10,6 +10,6 @@ class Email < ActiveRecord::Base
   validates_uniqueness_of :email
 
   def self.for_newsletter
-    find(:all, :conditions => ['receive_newsletters = ?', true])
+    find(:all, :conditions => ['receive_newsletters = ? AND email != ?', true, ''])
   end
 end