python 3: unicode vs str

See python3porting.com :)
python 3: no more dict.itervalues()

Replace with a helper (2to3 is too expensive!)
python 3: no more 'new'; port to type(x, y, z) instead
python 3: replace 'long' with numbers.Integral
python 3: mismatched types might not compare safely

The test which sets up an enum with integers and tuples as values fails
here in this deprecated block because the values don't compare.  Just skip
that if it happens; it's probably a silly case anyway.
python 3: metaclass support

Use the 'six' with_metaclass helper.  The exception must handle a new type
of virtual base class; make it generic while we're here.  ie, a 'RichEnum'
sub-class can define __virtual__ to suppress this exception.
python 3: replace __cmp__ with a __lt__

The total_ordering wrapper is a no-op on python 3.
Drop deprecated property 'choices' strict ordering requirement

This was sporadic on Python 3 and a deprecated field, so just make sure
all fields are present.
Release engineering for 1.1.0

Changelog, add trove classifiers to setup.py, and complete
the tox.ini