[ixpmanager] ixf member-export failing

[Jay Hanke]

> Not as it stands. It's JSON so it would be easy to wrap it and filter it
> yourself in a tiny PHP script.

I reached out to arouteserver devs and there is a --routeserver-only
option that can be added to the clients-from-euroix command that will
perform the filter.

They are going to update a future version of the script to accommodate
it by default.