CI build does not fail when tests fail. Fix #1527

problem: new field is breaking existing code

problem: user cannot poll on thread safe sockets

fixed issue with ticket #1517 (wrong lib output name in MSVC CMake bu…

fixed issue with ticket #1517 (wrong lib output name in MSVC CMake build) and apply some improvements in CMake build system

changing some camelCase variable names to snake_case in previous commit

remove unnecessary multiple WSAGetLastError() calls

place a ZMQ_UNUSED macro and replace all unused variables with ZMQ_UNUSED macro

Problem: Missing src/ prefix for libzmq library in Makefile.am ...

Solution: Add prefix to fix test compilation

Problem: lack test case for large stream messages

Merge fix for zeromq/zeromq4-1#52, getsockopt ZMQ_RCVMORE now resets all bits

Check proxy return values in tests

Solution: specify the necessary EXTRA_DIST

I added a Makefile.am in builds that covers all systems except msvc,
which already has a Makefile.am that does this.

Fixes #1505

Solution: fix it. Default is true, not false.

Solution: added to test_stream.cpp

fix: ZMQ_TCP_RETRANSMIT_TIMEOUT not applied to bind socket

Avoid terminating connections prematurely

While sending very large messages (far beyond what fits in a the tcp
buffer, so it takes multiple sendto system calls for it to finish),
zmq_close will close the connection regardless of ZMQ_LINGER.

In case no engine is attached, a pipe->check_read() is needed to look
for the delimiter in the pipe and ultimately trigger the pipe
termination.

However, if there *is* an engine attached, the check_read() looks ahead
and finds the delimiter and terminates the connection even though the
engine might actually still be in the middle of sending a message.

This happens because while the io_thread is still busy sending the data,
the pipe can get terminated and the io thread ends up being terminated.

add ZMQ_TCP_RETRANSMIT_TIMEOUT socket option