Stream access from Connection object

[mikasoukhov]

Sometimes need to transfer large files. Right now PipeConnection does not provide the ability to work with Stream. It means a response side should upload part of files into memory.

[HavenDV]

Yes, this is a useful feature. Initially, the library was created for simple transfer of objects using serialization and work with Stream occurs at a low level.
At the moment I do not have enough time to implement, either more requests for this feature are needed, or you can provide your current code as a PR.