This allows users to build drools-pdp and drools-applications docker images using their own CI pipelines without forking the upstream code.

drools-applications uses the script [deploy-artifact|https://github.com/onap/policy-drools-pdp/blob/master/policy-management/src/main/server-gen/bin/deploy-artifact] to install the packaged jars into local maven repo. In order to do so it uses [standalone-settings.xml|https://github.com/onap/policy-drools-pdp/blob/master/packages/base/src/files/etc/m2/standalone-settings.xml]. Hence, to allow users to build these docker images internally, parametrizing proxy settings and repo url details into the maven settings is very useful.