Investigate if the InstallerDB could be replaced with something simpler

For integration test execution the InstallerDB is used to populate the database.

To populate the database a create.sql file must be present.

The InstallerDB parses and analyzes this file. The parser does not understand ALL SQL statements and fails in a lot of ways (e.g. too few or too many whitespaces).

It would be ideal if we could replace the InstallerDB in general.

For this we should investigate:

 * if it can actually be removed

 * if it is used in some way other than setting up the database while testing