RADAR-base/RADAR-Schemas: radar-schemas version 0.5.0

Changes since version 0.4.3 - <ul> <li>Update to Java 11.</li> <li>Schema Topic Management - it is now possible to back up the entire _schemas topic and to replace it with a correct one if it has become corrupted. This change was made to avoid corruptions as we encounter in RADAR-base once in a while.</li> <li>Fix optional fitbit activity log type.</li> <li>Added new empatica spec with sensor status topic.</li> <li>Add <code>timeNotification</code> to questionnaire completion log.</li> <li>Validate kafka conversion.</li> <li>Update PMD.</li> <li>Avoid int overflow in application_records_sent.</li> <li>Schema support for absolute locations</li> </ul&gt