Config: clean-up and document

[qligier]

We should clean up the MAG configuration (mag.*) and properly document it before releasing v1.0.0.

Related to:

• [ ] #178
• [ ] #154

Other points:

• mag.xds.retrieve.url should be mag.mhd.iti68.retrievePath and made relative (we already have mag.baseurl)
• mag.xds.retrieve.repositoryUniqueId should be mag.xds.repositoryUniqueId
• mag.audit should be removed, use ipf.atna instead
• mag.extpatienturl could be removed
• mag.client-ssl could be renamed (e.g. soap-mtls, or moved to mag.xds, mag.pix and mag.iua.ap
• mag.iua.ap should be mag.sts
• Unsure what mag.iua.sp is doing exactly
• Unsure why we need mag.mpi.oids.custodian
• Unsure why we need mag.mpi.oids.query
• The MAG could warn on unknown properties in the mag.* scope
• The configuration bean could be validated
• We could set up an automatic configuration documentation generator