Fix uses of retired builtins and builtin methods

In Python 3.x

- int and long types are unified. The unified type is called int.
- the text string type (unicode) is renamed to str.
- the byte string type (str) is renamed to bytes.
- chr returns a text string (i.e. str)
- xrange is renamed to range.
- dict.has_key() is removed
-

examples/base64_sem2.py

@@ -28,7 +28,7 @@ import hammer as h
 def bsfdig_value(p):
     """Return the numeric value of a parsed base64 digit.
     """
-    c = p if isinstance(p, (int, long)) else ord(p)
+    c = p if isinstance(p, h.INTEGER_TYPES) else ord(p)
     if c:
         if 0x41 <= c <= 0x5A: # A-Z
             return  c - 0x41