MARTE13 — Missing a property to PeriodicServerParameters

In some case, when PeriodicServerParameters are used to model the parameter of a PSS (Posix Sporadic Server). it's happen that in some cases some SoftwareSchedulable resources could have the same background priority. So, to identify which one must be executed we need another parameter : order

it is possible to add a property like this:

order: NFP_Integer to the PeriodicServerParameters DataType.