Adding Copy Artifact plugin to Jenkins

[Mike Burns]

I'm adding the Copy Artifact Plugin to Jenkins.  This is needed to copy
rpms and other files/artifacts from one build to another.  Specifically,
the ovirt-node build will generate ovirt-node and ovirt-node-tools rpms.
These rpms are needed to run the ovirt-node-iso build.

The addition will result in a brief outage of Jenkins while it restarts.

Thanks

Mike