Allow custom transport and MAC constructor arguments

[bobmourlam]

In the current buildTransportWithAdapter and buildMACLayer_T functions
you are limited to only passing in NEMId, PlatformServiceProvider* and RadioServiceProvider* (MAC) as constructor params for a custom transport or MAC layer.

This change uses a parameter pack to allow an arbitrary number of
arguments to be passed to the transport/MAC constructor. And by using
perfect forwarding there should be no additional cost in copying those
params to the transport instance.

For example, with this change you can do something like this:

class MyCoolTransport
{
public:
   MyCoolTransport(
      NEMId id, 
      PlatformServiceProvider* platformService, 
      int customVar1.
      const std::string& customVar2);
};

...

auto ret =
   transportBuilder.buildTransportWithAdapter<MyCoolTransport>(
      id,
      {},  // ConfigurationUpdateRequest
      platformendpoint,
      transportendpoint,
      42,
      "My Cool String");

See also this change. I don't intend to merge this, but used it to test the change to buildMACLayer_T.
bobmourlam/emane-embedded-example@3147d0f?w=1

Signed-off-by: Bob Mourlam bob.mourlam@gmail.com

[sgalgano]

Thanks for the pull. This is a great add. And thanks for making your test artifacts available.