Problem: no OBS _service and various packaging problems

Solution: add one similar to the one generated by zproject

Solution: name the binary package that ships the library libzmq5 to
adhere to the soname convention for RPMs

Solution: update manpages list and use wildcard where possible in the
spec file

Solution: target wildcard in the spec file to make maintenance
easier

Solution: build-depend on the libraries and add parameters in the
spec file

Solution: build-depend on the toolchain and call autoreconf in the
spec

Solution: stop autogenerating it and hard code version so that the
OBS build service can extract it and use it to build packages
automatically

Solution: import and adapt Debian's packaging code from
https://packages.debian.org/source/unstable/zeromq3
As noted in packaging/debian/copyright, these files are licensed
under the LGPL2+ and the copyright belongs to the authors listed in
the same file.

Fixing indentations related to commit #2071

Convert manual (locking and unlocking) mutexes to scoped mutexes for the case of unlocking mutex even if the protected operation throws an exception (#2071)

Linux provides accept4(2) which will return a socket with FD_CLOEXEC set
when called with the SOCK_CLOEXEC flag. So call this when available and
fall back to fcntl(..., FD_CLOEXEC) if not.

Problem: Travis CI OSX builds are broken

Solution: add a workaround to reinstall libtool. Travis hasn't fixed
the issue in a month, so time for a little hack until they sort it.

Problem: getifaddrs can fail with ECONNREFUSED

getifaddrs() can fail transiently with ECONNREFUSED on Linux.
This has been observed with Linux 3.10 when multiple processes
call zmq::tcp_address_t::resolve_nic_name() simultaneously.

Before asserting in this case, make 10 attempts, with exponential
backoff, given by (1 msec * 2^i), where i is the attempt number.

Fixes #2051

Minor fixes/changes in Win32/MSVC build system

Solution: correct path is ../src/windows.hpp. Also added automatic linking
of iphlpapi library if required and using MSVC

only if the library is found at a specific path

Solution: Search for libzmq.lib in ../bin/Win32/Debug/v120/dynamic, don't
know how to automatically search in correct path based on current build
configuration

Problem: parameter %1 set hard to build target and prevents the skipp…

Solution: removed Pause

modified build.bat for msvc to support non-pausing script-based instal…

Signed-off-by: Bernd Langpap <Bernd.Langpap@airbus.com>

Problem: MSVC warns about event monitoring functions converting SOCKET to int

Add missing Git ignores.

Send manual unsubscriptions on pipe termination in XPUB

Expect custom messages on both explicit unsubscription and pipe termination.

Copy instead of reference to a vector that gets reallocated.

Flush stderr buffer before calling zmq_abort in assert macros

On Windows, the written message does not seem to be guaranteed to be
written to stderr, in particular when stderr is redirected to a file. I
suppose this is because RaiseException terminates the process in a way
that does not give the CRT a chance to flush stdio buffers (or if it
does, there might be a problem when more than one CRT instance is linked
into the program and they overwrite each other's exception handler). Either
way, just make sure the assertion message ends up written to stderr to
ease diagnostics.

Problem: FD_SETSIZE not set to 16k for all build definitions