Fix shell error on vagrant provision

Vagrantfile

@@ -9,6 +9,7 @@ load File.expand_path(vagrantfile) if File.exists?(vagrantfile)
 
 Vagrant.configure('2') do |config|
   config.vm.synced_folder "./", "/vagrant", type: "rsync", rsync__exclude: [ '.vagrant', '.git', 'config/config.ini' ]
+  config.ssh.shell="/bin/sh"
 
   config.vm.network "forwarded_port", guest: 80, host: 8080, auto_correct: true
   config.vm.network "forwarded_port", guest: 443, host: 8443, auto_correct: true