Add user deletion date

Fixes #2734

app/schemas/models/user.coffee

@@ -284,6 +284,7 @@ _.extend UserSchema.properties,
   earned: c.RewardSchema 'earned by achievements'
   purchased: c.RewardSchema 'purchased with gems or money'
   deleted: {type: 'boolean'}
+  dateDeleted: c.date()
   spent: {type: 'number'}
   stripeCustomerID: { type: 'string' } # TODO: Migrate away from this property
 

server/users/user_handler.coffee

@@ -279,6 +279,7 @@ UserHandler = class UserHandler extends Handler
         obj = user.toObject()
         for prop, val of obj
           user.set(prop, undefined) unless prop is '_id'
+        user.set('dateDeleted', new Date())
         user.set('deleted', true)
 
         # Hack to get saving of Users to work. Probably should replace these props with strings

test/server/functional/user.spec.coffee

@@ -331,6 +331,7 @@ describe 'GET /db/user', ->
 describe 'DELETE /db/user', ->
   it 'can delete a user', (done) ->
     loginNewUser (user1) ->
+      beforeDeleted = new Date()
       request.del {uri: "#{getURL(urlUser)}/#{user1.id}"}, (err, res) ->
         expect(err).toBeNull()
         return done() if err
@@ -338,11 +339,11 @@ describe 'DELETE /db/user', ->
           expect(err).toBeNull()
           return done() if err
           expect(user1.get('deleted')).toBe(true)
+          expect(user1.get('dateDeleted')).toBeGreaterThan(beforeDeleted)
+          expect(user1.get('dateDeleted')).toBeLessThan(new Date())
           for key, value of user1.toObject()
-            if key is 'deleted'
-              expect(value).toEqual(true)
-            else if key isnt '_id'
-              expect(_.isEmpty(value)).toEqual(true)
+            continue if key in ['_id', 'deleted', 'dateDeleted']
+            expect(_.isEmpty(value)).toEqual(true)
           done()
 
 describe 'Statistics', ->