Fix duplicate host resource

In some circumstances, the puppet-coe class may cause a duplicate
resource error due to host definition clashing with
puppet_openstack_builder's setup.pp manifest.  This patch prevents
the problem by creating the host entry with create_resource
instead of creating it explicitly.

Closes-Bug: #1292772
Merge pull request #44 from CiscoSystems/bugs/1292772

Fix duplicate host resource