Fixed potential SEGFAULT.
Merge remote-tracking branch 'upstream/master'
Merge pull request #922 from horus42/master

Fixed potential SEGFAULT in socket_base.cpp
Revert "Fixed potential SEGFAULT."

This reverts commit 79b81f48402c1276d4cfd3bf0cbfb4084952b36b.
Was causing:

Assertion failed: destroyed (socket_base.cpp:154)
/bin/bash: line 5: 31344 Aborted                 ${dir}$tst
FAIL: test_many_sockets

On TravisCI.
Merge pull request #923 from hintjens/master

Revert "Fixed potential SEGFAULT."
Merge pull request #924 from bebopagogo/master

NORM protocol extension
Fixed comment
Merge pull request #925 from hintjens/master

Fixed comment
Merge pull request #926 from bebopagogo/master

added uncommitted norm_engine changes
Fix cmake build on windows.
Fix travis build.
Fix travis build.
Fix tabs
Merge pull request #927 from ricnewton/master

Fix cmake build on windows & travis build.
Merge pull request #928 from bebopagogo/master

fixed another missed norm_engine issue for non-norm build
Add vs2013 solution and build for (v120) of libzmq project.
Add delays in test_connect_rid to allow time for socket to close before address reuse.
Fix tabs
Merge pull request #930 from ricnewton/master

Add delays in test_connect_rid
Fixed wrong assert in zmq_recv

zmq_recv returns bytes count, not error code, so 'assert (rc==0)' behaved completely wrong