Consistant parsing of attr_lists in Python3.3

Fixes #194.  The NAME_RE regex was failing in Python 3.3 with the range
`\u10000-\ueffff`. Also, in Python =< 3.2 the range `\u0300-\u036f` matches
a colon but not in Python 3.3.
Missed a set.append -> set.add.
Update tests to only run on supported versions of python.