Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

The new option allows user to guard against peers sending
oversized messages. Connection to peer sending oversized message
is dropped.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Patch to handle nmap version probes.
Signed-off-by: Dhammika Pathirana <dhammika@gmail.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Dhammika Pathirana <dhammika@gmail.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Dhammika Pathirana <dhammika@gmail.com>

This commit introduces the necessary changes necessary
for implementing flow control. None of the socket types
implements the flow control yet. The code will crash when
the flow control is enabled and the thw lwm is reached.

The following commits will add flow-control support for
individual socket types.

zmq_encoder/decoder are able to add/trim prefixes from messages; fair queueing and load balancing algorithms factorised into separate classes

messages that may have been received in the init phase are flushed immediately after engine is plugged in