Re: Trellis + Python 2.6

> Issue 1:
> UserList.UserList now has a metaclass, so trellis.List needs to
> redefine its metaclass to inherit from it

> Issue 2:
> trellis.py imports `sets` module which is deprecated and results in a warning.

Issue 3:

peak\events\trellis.py:511: DeprecationWarning: object.__new__() takes
no parameters
  return ReadOnlyCell.__new__(cls, rule, value, discrete)


If you don't have py2.6 installed, let me know and I'll send the patch
with relevant changes.