Add the 'bool' type and its values 'False' and 'True', as described in

PEP 285.  Everything described in the PEP is here, and there is even
some documentation.  I had to fix 12 unit tests; all but one of these
were printing Boolean outcomes that changed from 0/1 to False/True.
(The exception is test_unicode.py, which did a type(x) == type(y)
style comparison.  I could've fixed that with a single line using
issubtype(x, type(y)), but instead chose to be explicit about those
places where a bool is expected.

Still to do: perhaps more documentation; change standard library
modules to return False/True from predicates.

Lib/difflib.py

@@ -976,11 +976,11 @@ def IS_LINE_JUNK(line, pat=re.compile(r"\s*#?\s*$").match):
     Examples:
 
     >>> IS_LINE_JUNK('\n')
-    1
+    True
     >>> IS_LINE_JUNK('  #   \n')
-    1
+    True
     >>> IS_LINE_JUNK('hello\n')
-    0
+    False
     """
 
     return pat(line) is not None
@@ -992,13 +992,13 @@ def IS_CHARACTER_JUNK(ch, ws=" \t"):
     Examples:
 
     >>> IS_CHARACTER_JUNK(' ')
-    1
+    True
     >>> IS_CHARACTER_JUNK('\t')
-    1
+    True
     >>> IS_CHARACTER_JUNK('\n')
-    0
+    False
     >>> IS_CHARACTER_JUNK('x')
-    0
+    False
     """
 
     return ch in ws