Updated the work log.
Updated the work log.
Updated the work log.
Updated the work log.
Updated the work log.
Updated AppSpringConfig.jpaVendorAdapter() to work for any DB platform.

... at least, I think. I'm pretty sure it can auto-detect the correct
value for its 'database' property, so I'm leaving that unset for now.
Updated the work log.
Issue #24: Added PostgreSQL setup instructions to README-DEVENV.
Completes #24: Added PostgreSQL support.

Reworked the DAO tests to also cover PostgreSQL (on top of HSQL), and
also manually ran all of the application's other integration tests
against it to verify that everything still works.