Return Serializable back

Author: pomadchin

core-scala/src/main/scala/io/pdal/pipeline/package.scala

@@ -16,6 +16,4 @@
 
 package io.pdal
 
-package object pipeline extends json.Implicits with syntax.Implicits {
-  import io.pdal.pipeline.test._
-} // with Serializable
+package object pipeline extends json.Implicits with syntax.Implicits with Serializable