Fix scale-util for RFC 8040

The tool has multiple issues. It cannot correctly stop and start Karaf container.
In addition it is still using draft-bierman-netconf-restconf-02 noauth feature.
To update to RFC 8040 feature a proper authorization needs to be implemented in the tool.

Required things to do:

1. (ScaleUtil.java) change installed RESTCONF feature to "odl-restconf-nb-rfc8040"
2. (ScaleUtil.java) update requests paths according to: RFC 8040 version
3. (ScaleUtil.java) use credentials for request auth (avoid 401)

4. verify scale util works:

java -jar scale-util-2.0.12-SNAPSHOT-scale-util.jar --distribution-folder ../../../../karaf/target/assembly/ --controller-auth-username admin --controller-auth-password admin

5. verify default auth for the requests works

Try to make to work this command:

java -jar scale-util-2.0.12-SNAPSHOT-scale-util.jar --distribution-folder ../../../../karaf/target/assembly/

It means that admin:admin is the default username and password in parameters.

6. do clean-up

Remove ScaleUtilParameters.java class