Sending HTTP traffic to an RPC port panics

[zombiezen]

(h/t to @bcspragu for discovering)

If you send an HTTP GET onto an RPC port, the decoder panics when trying to allocate a large header. This is much more likely to panic on GOARCH=386 or other platforms where int is 32 bits wide.

Decode should have user-configurable limits on how much it reads from the stream, but we should also prevent a high number of segments, since even the header can overflow.