Added puppetenterprise broker

This broker can download a puppet enterprise package (the second item
in the servers array will be used as the URL) and install by generating
a puppet installer answer file with the appropriate puppet server.
Cert name will be `hostname -f`.
Added precise_nohostname model template

This model template skips the first boot setting of the hostname since
I would rather the hostname is set from the installer (which should get
it either from DHCP or by doing a reverse DNS lookup.
Updated puppetenterprise broker to support new req_metadata_hash
Fixed uri import
Added redhat_5 model template
created redhat 6_nohostname model
Merge branch 'redhat_5' into uow
Merge branch 'redhat_6_nohostname' into uow