NO-JIRA: system_test.py rename "agent" as "management" for management proxy.

git-svn-id: https://svn.apache.org/repos/asf/qpid/dispatch/trunk@1610837 13f79535-47bb-0310-9956-ffa450edef68
NO-JIRA: Fix logging in python_embedded.c - corrupting messages with printf substitutions.

Messages from python with sequences that are valid printf substitutions (e.g. "%s")
were printing garbage for the substitutions.

git-svn-id: https://svn.apache.org/repos/asf/qpid/dispatch/trunk@1610838 13f79535-47bb-0310-9956-ffa450edef68