Fix logging configuration

ODL Oxygen uses log4j2, which has a different configuration format
from log4j.  The org.ops4j.pax.logging.cfg that we were installing
was in log4j format, which is what caused logging to break.

The old format also created a large number of log files for each node
executed.  In this commit, we no longer create separate log files for each
dg / node.  We do, however, add the current directed graph and node id to each line logged in karaf.log

Change-Id: I1377efa7e0c6fa6963e18370d69bafab60ba024d
Issue-ID: CCSDK-427
Signed-off-by: Timoney, Dan (dt5972) <dt5972@att.com>