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.

@import url(style.css);

body { padding: 0;}
body > .header,
body > .footer
{
  margin: 0;
}
body .content { width: auto;}
.header h1 { font-size: 110%; }

table.classhelp th
{
  border-top: 1px solid #afafaf;
  border-bottom: 1px solid #afafaf;
  empty-cells: show;
  text-align: left;
  vertical-align: middle;
  white-space: nowrap;
}

table.classhelp td
{
  border-bottom: 1px solid #efefef;
  empty-cells: show;
  text-align: left;
  vertical-align: middle;
  white-space: nowrap;
}