Adds a Zaqar publisher

This adds a new publisher supporting samples and events which can be
used in the pipelines.

Change-Id: I5f95228c38656522a14b20370e2cfd67cb911f80

tox.ini

@@ -4,7 +4,7 @@ skipsdist = True
 envlist = py{27,35},{debug,py,py27,py35}-{mongodb,mysql,postgresql,functional},pep8
 
 [testenv]
-deps = .[mongo,mysql,postgresql,gnocchi]
+deps = .[mongo,mysql,postgresql,gnocchi,zaqar]
        -r{toxinidir}/test-requirements.txt
 # NOTE(tonyb): This project has chosen to *NOT* consume upper-constraints.txt
 install_command = pip install -U {opts} {packages}