remove reference to required IP in readme
remove reference to required IP in readme

since it's no longer required!

LalatenduMohanty/landrush,njam/landrush,phusion/landrush,mheiges/landrush,phinze/landrush,vagrant-landrush/landrush,strzibny/landrush,vagrant-landrush/landrush,sneal/landrush