INFRA-266 Improve patient-db loaders

[mdenburger]

Several small improvements and additions to patient-db that make it possible to run the loader classes as separate processes in an automated way:

• Let all loaders return exit code 1 on failure.
• Let all loaders use try-with-resources to close the database connection on failure.
• Add class CheckSampleExistsInDatabase, which is used by automation to check whether a sample already exists.
• Add a -sample parameter to LoadCuppa2. Using the TSV header doesn't work since that's often just "sample_1" instead of the real sample ID.

Also removed the "shade" profile, which is no longer needed when the patient-db.jar is run as a separate process.

[mdenburger]

Good idea to revert the check, I've changed it to CheckSampleAbsentFromDatabase.