Update packages.pp

Added RHEL version 7, otherwis we get "No matching value for selector param '7' at /etc/puppet/modules/portmap/manifests/rhel/services.pp:11"
Added RHEL 7 support

Added RHEL version 7, otherwise we get "No matching value for selector param '7' at /etc/puppet/modules/portmap/manifests/rhel/services.pp:11"
Merge pull request #10 from Netbulae/master

Added RHEL 7 support