We need to initialize migrations here as well.

src/java/com/samskivert/jdbc/depot/DepotMarshaller.java

@@ -843,6 +843,7 @@ public class DepotMarshaller<T extends PersistentRecord>
         for (EntityMigration migration : _migrations) {
             if (!migration.runBeforeDefault() &&
                 migration.shouldRunMigration(currentVersion, _schemaVersion)) {
+                migration.init(getTableName(), _fields);
                 ctx.invoke(migration);
             }
         }