Merge pull request #659 from hintjens/master

Problem: dropped & in last patch, causing segfault
zhash msvc build fixes
Merge pull request #660 from jossgray/msvc_build_fixes

zhash msvc build fixes
Revert "zhash msvc build fixes"

This reverts commit 4f78d78967af511e399a1c37463f16117bdcb4f2.
Revert "Problem: zhash public API was broken"

This reverts commit e337e2d8973e6d74b0cdf73332abae99bb0e1884.

Conflicts:

	src/zhash.c
zhash: Use const void * for keys to remain compatible with const char *
Merge pull request #662 from Q-Leap-Networks/pull-zhash-void-key

Pull zhash void key
zuuid: check for errors in constructor
zthread: Assert context creation
zthread: assert zstr_recv returns a string
zstr: assert message creation
zstr: assert zstr_recv returns a string
zsock: check creation in constructors
zsock: check zsys_vprintf returns a string
zsock: check zmsg_addmem succeeds
zsock: assert constructors succeed in test
zmsg: Use destructor when constructor fails
zmsg: Check creating zframe succeeds
zmsg: check allocating buffer for encoding succeeds
zlist: duplicate destructor and duplicator only when creating copy succeeds