This is a skeleton plugin i.e. the minimal plugin boilerplate.
It adds an owner and message mapping key and print it when reading or writing the parameter.
It has no purpose: it only serves as a template and the make install target does not install it. If you want to see a real-life plugin and makefiles, see https://github.com/01org/parameter-framework-plugins-alsa or https://github.com/01org/parameter-framework-plugins-filesystem instead.