Expose sign-up date as an user attribute in the editor.

services/web/app/coffee/Features/Project/ProjectController.coffee

@@ -245,6 +245,7 @@ module.exports = ProjectController =
 						first_name : user.first_name
 						last_name  : user.last_name
 						referal_id : user.referal_id
+						signUpDate : user.signUpDate
 						subscription :
 							freeTrial: {allowed: allowedFreeTrial}
 						featureSwitches: user.featureSwitches