Need to wrap filter call in list because we can't user an irritator a…

…s package metadata.

setup.py

@@ -131,7 +131,7 @@ def read_file(*path):
       license = "ZPL 2.1",
       platforms = ["any"],
       description = doclines[0],
-      classifiers = filter(None, classifiers.split("\n")),
+      classifiers = list(filter(None, classifiers.split("\n"))),
       long_description = long_description,
       test_suite="__main__.alltests", # to support "setup.py test"
       tests_require = tests_require,