New UI-resizing interface.

Changed the way wrapping is done when getting an explicitly-wrapped
object from an implicitly-wrapped object to avoid an extra level of
wrapping.

Fixed a bug that prevented propigation of some filtering errors.

by returning None, rather than 0.

non-binary pickle floats.

  - Properly propigate traceback from ExternalMethod, and

  - Use standard_error_message.

to quote strings.