minor fixes for migration

ebean-ddl-generator/src/main/java/io/ebeaninternal/dbmigration/DbMigrationPlugin.java

@@ -37,7 +37,7 @@ public class DbMigrationPlugin implements Plugin {
         lastInit = dbMigration.generateInitMigration();
       }
     } catch (IOException e) {
-      throw new RuntimeException("Error while generating migration");
+      throw new RuntimeException("Error while generating migration", e);
     }
   }
 

ebean-ddl-generator/src/main/java/io/ebeaninternal/dbmigration/DefaultDbMigration.java

@@ -13,6 +13,7 @@ import java.util.StringJoiner;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import io.avaje.classpath.scanner.core.Location;
 import io.ebean.DB;
 import io.ebean.Database;
 import io.ebean.annotation.Platform;
@@ -863,7 +864,8 @@ public class DefaultDbMigration implements DbMigration {
   }
 
   private String migrationPath(boolean initMigration) {
-    return initMigration ? migrationInitPath : migrationPath;
+    // remove classpath: or filesystem: prefix
+    return new Location(initMigration ? migrationInitPath : migrationPath).path();
   }
 
   /**