Delete DEFAULT_SERVER_URL (#135)

Author: Nate Foster

P4D2_2018_East/vm/Vagrantfile

@@ -1,8 +1,6 @@
 # -*- mode: ruby -*-
 # vi: set ft=ruby :
 
-Vagrant::DEFAULT_SERVER_URL.replace('https://vagrantcloud.com')
-
 Vagrant.configure(2) do |config|
   config.vm.box = "bento/ubuntu-16.04"
   config.vm.define "p4-tutorial" do |tutorial|