Solution: do it

This reverts commit fd27324e.

Solution: migrate to unity

Solution: apply naming style

Solution: applied clang-format

Solution: use "routing_id" instead

Solution: split each stat into its own frame, to make it simpler and
easier to use it, especially from high level bindings

Solution: ifdef it until it's declared stable

Solution: trucate 64 bit stats in test_proxy, as it's much easier than
to try and print 64 unsigned integers in a portable way

* Issue #2736: Add STATISTICS command to zmq_proxy_steerable()

Solution: use ZMQ_LAST_ENDPOINT in most places. This alllows running
tests in paralle, and on over-booked shared machines where many of
the ports would be already in use.
Keep 3 tests with an hardcoded port, as there are some code paths that
require it (eg: connect before bind), but list those ports in
tests/testutil.hpp as macros so that they do not overlap and still
allow parallel runs.

These changes were inspired by a patch uploaded to Ubuntu by the
package maintainer, Steve Langasek <steve.langasek@ubuntu.com>.
Thank you Steve!

Solution: remove all remaining references to `zmq_utils.h`

Solution: update to 2016

Of course people still "can" distributed the sources under the
LGPLv3. However we provide COPYING.LESSER with additional grants.

Solution: specify these grants in the header of each source file.

Solution: update for 2015

Fixes #1320

This reverts commit 2a84d259.

Broke regression test on test_hwm.cpp.

These changes cause an assertion in lb_sendpipe() when executing the test_security_plain testcase.

This reverts commit 9ae6a91f.

- used msleep (10) in most places instead of zmq_sleep (1)
- may cause failures on slower machines
- to change, modify SETTLE_TIME in testutil.h
- tested down to 1 msec on fast boxes