message: iHdlObj.origin prop. for backward references in code generators
diff: @@ -13,12 +13,15 @@ class iHdlObj(object):
  Object with direct representation in HDL
  :ivar ~.doc: doc from the HDL related probably to this object
  + :ivar ~.origin: an object which is responsible for this HdlObject
  + (not used by this library, used in user code)
  """
  - __slots__ = ["doc", "position"]
  + __slots__ = ["doc", "position", "origin"]
  def __init__(self):
  self.doc = "" # type: str
  self.position = None # type: Optional[CodePosition]
  + self.origin = None
  def __repr__(self):
  from hdlConvertor.to.json import ToJson
  