Add comments on Proxying to README

[grtjn]

See http://justintung.com/2013/04/25/how-to-configure-proxy-settings-in-linux/ for some interesting suggestions..

[jongiddy]

I used the vagrant-proxyconf plugin and added this to the the Vagrantfile:

     mastername = get_vm_name(1)

+    hostnames = (1..@nr_hosts).map{|i| get_vm_name(i)}.join(",")
+    config.proxy.ftp      = "http://10.1.1.100:8080/"
+    config.proxy.http     = "http://10.1.1.100:8080/"
+    config.proxy.https    = "http://10.1.1.100:8080/"
+    config.proxy.no_proxy = "localhost,127.0.0.1,#{hostnames}"
+  
     config.hostmanager.enabled = false
     config.hostmanager.manage_host = true
     config.hostmanager.include_offline = true

Would it be worth adding this code inside a guard expression and having the proxy as an optional setting in project.properties?

[grtjn]

Looks great! PR's always welcome.. :)