Error handling in backends.

I would vote for not having GUI messages being popped up from

    > a script. A quick poll of our users also indicates that they
    > expect script errors to be like python and appear in the
    > script.

Agreed -- what designed to ease the life of point and click windows
users has turned into a monster that is bogging us down.

    > Could we set some type of option in the config file that
    > would allow either behavior?

No, afraid not. All that crappy error handling cruft is going in the
heap. It's exceptions all the way through.

I've actually already banished every usage of error_msg from my local
tree. I think verbose.report_error should go the same way -- all
opposed, say "Nay"!

Assuming that report_error should die too, the remaining question is
how to best handle deprecation or non fatal errors
or something where we want to warn but fall back on a default
behavior. My vote is

  import warnings
  warnings.warn('This function is deprecated')