Fixes #663
Problem: zproto changed some class properties

Solution: track changes and regenerate code.
Merge pull request #664 from hintjens/master

Fixes #663
adding zsock_pollin
changing zsock_pollin to zsock_waiting
Merge pull request #665 from taotetek/master

Problem: creating pollers in language bindings for CZMQ is difficult
adding zsock_ready to compliment zsock_waiting
Merge pull request #666 from taotetek/master

Problem: we can easily check for POLLIN on a zsock but not POLLOUT
making names more explicit and fixing a bug in pollout (formerly ready)
Merge pull request #667 from taotetek/master

Problem: names weren't explicit
Cleaned-up and fixed zsock_ready/waiting code

- proper indentation and hyphens for header
- zsock_ready() was testing ZMQ_POLLIN
Problem: zsock_waiting code is too complex

Solution: just test zsock_event()

In fact these two methods could probably be removed without harm.
Merge pull request #668 from hintjens/master

Cleaned-up and fixed zsock_ready/waiting code
removing zsock_pollin and zsock_pollout
Merge pull request #669 from taotetek/master

Problem: new methods added complexity with no functionality gain
zpubsub implemented, with examples and doc
Added zpubsub_option class; using options in zpubsub.
Merge branch 'zpubsub'

Finished work on the zpubsub class, with corresponding zpubsub_option
static companion class.
Added check for broadcast interface in zpubsub_test, skipping system test
if no broadcast interface is available.
Merge pull request #670 from lovmoen/master

zpubsub class