Add helper class for core network handling in CI

This adds a helper class to manage various core networks in the CI
testing framework. Specifically, it reads from a YAML file information
such as a node, (un-)deployment script (file), log collection
instructions, etc., in order to allow a common interface to be used to
deploy and undeploy various core network implementations.

This commit adds the class (in cls_corenetwork.py) as well as tests for
this class.

ci-scripts/tests/scripts/deploy-core.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+function die() {
+	echo $@
+	exit 1
+}
+
+echo "deployment from script"
+
+[ $# -gt 0 ] && die "failing"
+
+exit 0