Fixes #4450, add another expand_path ../ to get back to the guests directory

[andytson]

When installing from master after #4438 fix was in, I get the following error, which this PR fixes:

vagrant up test7
Bringing machine 'test7' up with 'virtualbox' provider...
==> test7: Importing base box 'opscode-centos-7.0'...
==> test7: Matching MAC address for NAT networking...
==> test7: Setting the name of the VM: test7
==> test7: Clearing any previously set network interfaces...
==> test7: Preparing network interfaces based on configuration...
    test7: Adapter 1: nat
    test7: Adapter 2: hostonly
==> test7: Forwarding ports...
    test7: 22 => 2222 (adapter 1)
==> test7: Running 'pre-boot' VM customizations...
==> test7: Booting VM...
==> test7: Waiting for machine to boot. This may take a few minutes...
    test7: SSH address: 127.0.0.1:2222
    test7: SSH username: vagrant
    test7: SSH auth method: private key
    test7: Warning: Connection timeout. Retrying...
==> test7: Machine booted and ready!
==> test7: Checking for guest additions in VM...
==> test7: Setting hostname...
==> test7: Configuring and enabling network interfaces...
==> test7: Forcing shutdown of VM...
==> test7: Destroying VM and associated drives...
/path/to/gems/vagrant-1.6.4/plugins/guests/redhat/cap/configure_networks.rb:26:in `require': cannot load such file -- /path/to/gems/vagrant-1.6.4/plugins/guests/redhat/fedora/cap/configure_networks (LoadError)
  from /path/to/gems/vagrant-1.6.4/plugins/guests/redhat/cap/configure_networks.rb:26:in `configure_networks_rhel7'
  from /path/to/gems/vagrant-1.6.4/plugins/guests/redhat/cap/configure_networks.rb:17:in `configure_networks'

[mitchellh]

Thanks. :)

[andytson]

I think I should probably avoid # referencing in commits, as the merge closed the referenced issue that is still an issue for RHEL7 (though not CentOS7)