Improve error message when oracle configured without oracle support

I mistakenly tried to run CI on CTA compiled without oracle support:

[root@init /]# cta-catalogue-schema-drop /etc/cta/cta-catalogue.conf 
Aborting: create failed: Unknown database type: value=1

[root@init /]# rpm -qf /usr/bin/cta-catalogue-schema-drop
cta-catalogueutils-4-4729045git5e6645c8.el7.cern.x86_64

The message is very confusing as it looks like a parsing error when the underlying issue is that oracle is not supported for this binary.

Something like ERROR: trying to configure oracle backed catalogue on a CTA binary compiled without oracle support. would be much better.