Merge pull request #711 from lovmoen/master

zpubsub in labs area compiles to object files.
Problem: Cumbersome to compile z* files in labs folder

Solution: Changed the autotools configuration

Prerequisites: libczmq is installed

Step 1: ./configure --enable-labs=yes
Step 2: make
Step 3: make install

Know you've got a library libczmq_labs installed on your system which
can be used in third party projects.
Merge pull request #713 from sappo/master

Problem: Cumbersome to compile z* files in labs folder
Problem: There's no example on how to use labs library

Solution:

* modify the zpubsub simple example to link against labs library.
* update the README.txt with Step by Step setup.
Merge pull request #714 from sappo/master

Problem: There's no example on how to use labs library
Problem: No consistent code format.

Solution: Use uncrustify code formatter.
Merge pull request #715 from sappo/master

Problem: No consistent code format.
Revert "Problem: No consistent code format."
Merge pull request #716 from zeromq/revert-715-master

Revert "Problem: No consistent code format."