Rudder

Some part of the DSC code are DSC specific and should not impact the main Rudder branch.

Typically, having all the known type of Agent in Rudder core or other extremelly stable data types be OK (a new agent kind is expected to bring major evolution in Rudder architecture, and it is ok to have some internal code knowing what is supported), but how to specifically write a DSC policy should not (we certainly don't want to be force to update Rudder version to change that kind of things).