HTTP pipelining is always disabled

[Archie3d]

I've noticed on http streams pipelining is always disabled and all the range request sent by the client are unconstrained:

Range: bytes 0-

I believe this is because the client never sends Connection: Keep-Alive in op_http_stream_open() along with the other headers.
Once added, the pipelining seems to work and the client issues well constrained range requests.