Merging the py3k-pep3137 branch back into the py3k branch.
No detailed change log; just check out the change log for the py3k-pep3137
branch.  The most obvious changes:

  - str8 renamed to bytes (PyString at the C level);
  - bytes renamed to buffer (PyBytes at the C level);
  - PyString and PyUnicode are no longer compatible.

I.e. we now have an immutable bytes type and a mutable bytes type.

The behavior of PyString was modified quite a bit, to make it more
bytes-like.  Some changes are still on the to-do list.
diff --git a/Lib/test/test_asynchat.py b/Lib/test/test_asynchat.py
index 78f5868..83b0972 100644
--- a/Lib/test/test_asynchat.py
+++ b/Lib/test/test_asynchat.py
@@ -105,17 +105,17 @@
     def test_line_terminator1(self):
         # test one-character terminator
         for l in (1,2,3):
-            self.line_terminator_check(b'\n', l)
+            self.line_terminator_check('\n', l)
 
     def test_line_terminator2(self):
         # test two-character terminator
         for l in (1,2,3):
-            self.line_terminator_check(b'\r\n', l)
+            self.line_terminator_check('\r\n', l)
 
     def test_line_terminator3(self):
         # test three-character terminator
         for l in (1,2,3):
-            self.line_terminator_check(b'qqq', l)
+            self.line_terminator_check('qqq', l)
 
     def numeric_terminator_check(self, termlen):
         # Try reading a fixed number of bytes