update for clhep (#4588)
update for clhep (#4588)

* adding clhep 2.3.4.4, etc and modernizing package.py

* add remaining 2.3.x.y clhep releases

* setting list_depth to 1 is sufficient

* remove whitespace

tmerrick1/spack,skosukhin/spack,mfherbst/spack,TheTimmy/spack,lgarren/spack,tmerrick1/spack,lgarren/spack,matthiasdiener/spack,tmerrick1/spack,LLNL/spack,krafczyk/spack,skosukhin/spack,TheTimmy/spack,matthiasdiener/spack,matthiasdiener/spack,matthiasdiener/spack,EmreAtes/spack,LLNL/spack,mfherbst/spack,tmerrick1/spack,iulian787/spack,tmerrick1/spack,EmreAtes/spack,TheTimmy/spack,TheTimmy/spack,krafczyk/spack,matthiasdiener/spack,EmreAtes/spack,lgarren/spack,krafczyk/spack,skosukhin/spack,mfherbst/spack,iulian787/spack,krafczyk/spack,lgarren/spack,iulian787/spack,LLNL/spack,skosukhin/spack,LLNL/spack,mfherbst/spack,iulian787/spack,EmreAtes/spack,skosukhin/spack,lgarren/spack,LLNL/spack,iulian787/spack,TheTimmy/spack,EmreAtes/spack,krafczyk/spack,mfherbst/spack