Refactor the libctacatalogue DB interface such that in can be build only with the chosen DB client library, either Oracle or Postgres.

Problem to solve

Currently CTA is linked with both Oracle and Postgres client libraries while we should require CTA to only be linked with the client libraries of the DB technology chosen at configuration time.

Stakeholders

This will increase the flexibility of the configure and build process.

Proposal

Add the proper conditional code in libctacatalogue to link or load only the required DB client libraries.