Solution: Don't allow concurrent heartbeat timers

Problem: behavior of closing a socket registered...

...in a poller is not documented.
Solution: Document it.

Problem: incorrect ZMQ_MAX_SOCKETS default value in doc

Solution: update the doc with the correct default value

CMake: Install debug libraries for debug msvc builds

problem: ws_engine duplicate code from stream_engine

Solution: New class called stream_engine_base which is inherited by ws_engine, zmtp_engine and raw_engine.

Problem: build on centos6/ubuntu12 still broken

Solution: move the definition of __STDC_LIMIT_MACROS somewhere the test actually uses

Problems: build broken on centos6/ubuntu12, missing licenses and wrong copyright dates

Solution: add it

Solution: fix them

Solution: define __STDC_LIMIT_MACROS before including stdint.h so that SIZE_MAX
is defined

Solution: add it and mention the inclusion in NEWS

problem: browser cannot communicate with zeromq directly

Use libsodium based allocator

Solution: properly set defines from test_security_curve

Solution: implement ZWS 2.0 which websocket transport for zeromq

Solution: Use secure_allocator_t for plaintext secrets

Solution: Added secure_allocator_t based on libsodium's memory management functions when available

Solution: Fixed C++ standard in clang-format config

Problem: unused parameter in benchmark function

Solution: remove it

Problem: use of malloc is error-prone

Static analysis warnings

Solution: use std::vector instead, simplify control-flow

Solution: set -e in ci_build.sh like in other scripts

Solution: don't write it

Solution: add them

problem: wrong api_key for bintray

Solution: update it

Free memory when curve_client sends invalid ready message.

Problem: Missing ZeroMQ_INCLUDE_DIR when only static lib is built

Problem: 4.3.2 is out, need new version

Solution: bump to 4.3.3