module-specific database schemas

[sventhiel]

Description
Currently, all tables of each module are created within the default PostgreSQL schema "public". In order to improve and ease the identification of the tables, the usage of different schemas (one for each module) was targeted.

After some investigations, it became clear that while this approach works, it has three significant drawbacks.

1. We were not able to automate the creation of different schemas at database creation time.
2. Instead of easing the work to look for specific tables, it got even worse because you would need to know in advance to which module the desired table belongs.
3. For some tables, determining the module is not easy (or even "impossible").

Conclusion
As before, we will not use different schemes in the database.