made some custom transport implementation possible

[sum-catnip]

Hey,

im using your library at work and i needed to make it linux compatible. I made some very minor changes that allowed me to make my own RpcConnectedClientTransport implementation. The changes made it possible to use the SMBLibrary as my transport method instead of the pinvoke/windows-dependant one. If you don't mind, it would be nice to have those changes in the main repo so:

1. others may benefit from making their own transport implementation
2. i don't have to maintain my own fork :p

Have a nice day :) Also thanks so much for creating this awesome project!

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[sum-catnip]

normally id publish the whole "linux implementation" but i only did the bare minimum as quickly as possible. Basically i just replaced the entire connect and bind part of this library with using SMBLibrary to connect and bind to a namedpipe. Then just used the pipes read and writefile functions for readfragment and writefragment. Thats i, but it works surprisingly well!