Fix string/bytes issues under python 3. 1) cgi/client.py: override cgi.FieldStorage's make_file so that file is always created in binary/byte mode. This means that json (and xml) are bytes not strings. 2) rest.py: try harder to find dicttoxml in roundup directory or on sys.path. This just worked under python 2 but python 3 only searches sys.path by default and does not search relative like python 2. 3) rest.py: replace headers.getheader call removed from python 3 with equivalent code. 4) rest.py: make value returned from dispatch into bytes not string. 5) test/caseinsensitivedict.py, test/test_CaseInsensitiveDict.py: get code from stackoverflow that implements a case insensitive key dict. So dict['foo'], dict['Foo'] are the same entry. Used for looking up headers in mocked http rewuset header array. 6) test/rest_common.py: rework tests for etags and rest to properly supply bytes to the called routines. Calls to s2b and b2s and use of BytesIO and overriding make_file in cgi.FieldStorage to try to make sure it works under python 3.

# misc tests

import unittest
import roundup.anypy.cmp_
from roundup.cgi.accept_language import parse

class AcceptLanguageTest(unittest.TestCase):
    def testParse(self):
        self.assertEqual(parse("da, en-gb;q=0.8, en;q=0.7"),
                         ['da', 'en_gb', 'en'])
        self.assertEqual(parse("en;q=0.2, fr;q=1"), ['fr', 'en'])
        self.assertEqual(parse("zn; q = 0.2 ,pt-br;q =1"), ['pt_br', 'zn'])
        self.assertEqual(parse("es-AR"), ['es_AR'])
        self.assertEqual(parse("es-es-cat"), ['es_es_cat'])
        self.assertEqual(parse(""), [])
        self.assertEqual(parse(None),[])
        self.assertEqual(parse("   "), [])
        self.assertEqual(parse("en,"), ['en'])

class CmpTest(unittest.TestCase):
    def testCmp(self):
        roundup.anypy.cmp_._test()