Allow to configure the host of the (remote) office server

If using a separate office server process (i.e. openoffice.serverType=1), the host on which that server runs if hard wired to 127.0.0.1. There are good reasons for this, namely that the libre-/openoffice software is not really designed to run as a server, and especially cannot handle concurrent requests. It makes little sense to open that service to the network …

… except in the docker world, where one usually has one container for one service, and this container talks to the other container via a local docker network (or so understood). In that case it is useful to be able to set up an external IP for the office server.

Are there any problems if I try to implement such a configuration option (i.e. openoffice.serverHost = ... ). Of course this should come with a big warning that this setting does not mean that the office service can be shared among XWiki instances (or any other clients) and is only present for the special case of communication between docker containers, and should be left at its default value otherwise.

So in theory I don’t see a problem with that, the only thing I’m not sure about is how would it work especially for images to be embedded. AFAIR we’re relying on the path on the local host to embed images, so you might have problems when exporting documents using a remote office server.