Use logbook zmq handler to centralize logging
I'm dropping the custom code that I wrote over "logbook":http://pythonhosted.org/Logbook/index.html, a library that after doing some tests seems to work really good and is easy to use.
(from redmine: created on 2015-06-12, closed on 2015-06-12, relates #7140 (closed), relates #7141 (closed), relates #7142 (closed), relates #7143 (closed), relates #7144 (closed), relates #6733 (closed), relates #7180 (closed))