Allow JCentral address override using environment variables
This is now needed for the JCentral replica, and we have similar feature in alien.py (ALIENPY_JCENTRAL
).
We used to do this by patching the jbox conf files in /tmp, but environment variables are easer to use in CI.
The variable used here is JALIEN_HOST
(as in the jclient file) and default value is of course alice-jcentral.cern.ch
.
We should synchronise all those environment variables at some point.