fix upload permissions introduced in raik:ufs 0.3.4

lib/fileUpload.coffee

@@ -74,13 +74,11 @@ if UploadFS?
 					token = cookie.get('rc_token', rawCookies) if rawCookies?
 
 					unless uid and token and RocketChat.models.Users.findOneByIdAndLoginToken(uid, token)
-						res.statusCode = 403
-						res.end('Not Allowed')
-						# Just to abort the request
-						# See https://github.com/jalik/jalik-ufs/issues/28
-						throw new Meteor.Error 403, 'Not Allowed'
+						res.writeHead 403
+						return false
 
 				res.setHeader 'content-disposition', "attachment; filename=\"#{ encodeURIComponent(file.name) }\""
+				return true
 
 Meteor.startup ->
 	if Meteor.isServer