#96 a mirror functonality

[Egon Willighagen]

It would be nice if AMBIT directly after installation of the .war had a functionality to mirror another database. The user of the new instance only needs to provide the URL of some remote database, and then the new instance will start populating itself with data from that remote instance, effectively mirroring the content. This mirroring would be friendly to the remote server and report progress to the user/admin of the local instance. I see no need the mirroring has to be fast and may take a day or two for huge databases. The implementation would use the existing API whenever possible.