We are unique

Some tiny improvements on the SimpleIPC Server for Amiga-style systems, ServerRunning was not implemented and UniqueInstance use the Message type to transfer the number of Parameter, so I had to implement this also.

Now its possible to use UniqueInstance functions in AROS also, without special ifdefs. (only a tiny change in the original unique instance code is needed an additional define ifdef Unix -> if defined(unix) or defined(HASAMIGA))

The code is available at GitHub