Fixed a bug where dellprod didn't match the string expected by the Dell OMSA repository.
dellprod is now has "pe" appended to the value returned by Facter.value(:productname).
Ex: r720 becomes per720

This should be improved because there are a few instances in the repo that don't use "pe":
dx6000, dx6012s, dx6004s

I'll look at adding this in a future release