Fix IPV6 support
Fix IPV6 support

In c3373e4, @danielsdeleo added support for IPV6, but I didn't understand
the purpose of the bracket notation. I thought they were part of the `host`,
but they are actually part of the URL. We _need_ the brackets in the URL,
but we _cannot_ have the brackets in the host.

lazyval/chef-zero,bitmonk/chef-zero,chef/chef-zero,chef/chef-zero,higanworks/chef-zero,h4ck3rm1k3/chef-zero,patcon/chef-zero,higanworks/chef-zero,bitmonk/chef-zero,lazyval/chef-zero,getoutreach/chef-zero,patcon/chef-zero,getoutreach/chef-zero,h4ck3rm1k3/chef-zero,chef/chef-zero