automatic plugin configuration from system properties

it'd be nice to have an automatic way to be able to derive a property that would set plugin configuration:

-Dplugin.<prefix>.<property>.<element>.<element>=<value>

eg,
-Dplugin.jar.finalName=foo
-Dplugin.jar.archive.manifest.addClasspath=true

Note that there are other considerations with system properties overriding config - it needs to be populated in the POM on release. We should consider this, or else allow a plugin to say which variables shouldn't be configured in this way (though I'd find that tedious and error prone)