INSPIRECodeListReader: use local resource as fall-back only

Change-Id: I1cd63e1c009fa8a976d8701d3b243b6d907c713a
Reviewed-on: http://gerrit.esdi-community.eu/3212
Tested-by: Jenkins <sitemple@igd.fraunhofer.de>
Reviewed-by: Simon Templer <simon.templer@igd.fraunhofer.de>