Added explanation to Flyway init

src/main/java/no/nibio/vips/coremanager/startup/StartupListener.java

@@ -41,7 +41,7 @@ public class StartupListener implements javax.servlet.ServletContextListener {
         System.out.println("VIPSCoreManager checking for database migrations");
         // Migrate DB on startup using flywaydb.org
         Flyway flyway = Flyway.configure()
-                .table("schema_version")
+                .table("schema_version") // This was done to ease the upgrade from v4 to v8 - which has "flyway_schema_history" as default name for this table
                 .dataSource(vipscoremanagerDS)
                 .load();
         flyway.migrate();