Added new online resource protocols pertaining to the three different ag...

...gregation methods now supported by the portal ecosystem, along with an example XML record which uses them.

Note: I have temporarily disabled https://jenkins.aodn.org.au/job/GeoNetwork/ otherwise merging this would result in new deployments to the various GeoNetwork instances we have.  Probably we should decouple the build and deployment stages (with some sort of manual trigger) as we have done for other projects.