Only keep localhost for 127.0.0.1

The regex used previously would keep the short hostname (hostname -s)
on the 127.0.0.1 line.

Reset the 127.0.0.1 line to keep only localhost.

TrivialFix

Change-Id: I90bdec6793ac5b2d304e178e5114369b7b3b9626

dev/vagrant/bootstrap.sh

@@ -61,7 +61,7 @@ function prep_work {
 
     # This removes the fqdn from /etc/hosts's 127.0.0.1. This name.local will
     # resolve to the public IP instead of localhost.
-    sed -i -r "s/^(127\.0\.0\.1\s+)(.*) `hostname` (.+)/\1 \3/" /etc/hosts
+    sed -i -r "s,^127\.0\.0\.1\s+.*,127\.0\.0\.1   localhost localhost.localdomain localhost4 localhost4.localdomain4," /etc/hosts
 
     if is_centos; then
         yum -y install epel-release