Change to mio-based non-blocking I/O

[osuketh]

libsgx-rs/remote-attestation/src/client.rs

Lines 98 to 102 in 8712a56

	pub fn send<T: Write>(&self, writer: &mut T) -> Result<Response> {
	self.request.send(writer)
	.map_err(|e| anyhow!("{:?}", e))
	.map_err(Into::into)
	}