[Zope] Persistent Mapping error with TinyTablePlus.

[Ignacio Valdes]

Hi Chris, When I try to change a Squishdot rightbox_items title or even not
change anything and try to save it out I get this error thrown:

Site Error

An error was encountered while publishing this resource.

NameError
Sorry, a site error occurred.

Traceback (innermost last):

  * Module ZPublisher.Publish, line 194, in publish_module_standard
  * Module Products.PlacelessTranslationService.PatchStringIO, line
34, in new_publish
  * Module ZPublisher.Publish, line 146, in publish
  * Module Zope2.App.startup, line 222, in zpublisher_exception_hook
  * Module ZPublisher.Publish, line 115, in publish
  * Module ZPublisher.mapply, line 88, in mapply
  * Module ZPublisher.Publish, line 41, in call_object
  * Module Products.TinyTablePlus.TinyTablePlus, line 446, in manage_editData
  * Module Products.TinyTablePlus.TinyTablePlus, line 509, in _GenerateIndex

NameError: global name 'PersistentMapping' is not defined (Also, the
following error occurred while attempting to render the standard error
message, please see the event log for full details:
'standard_html_header')