Update links and version info.

Doc/library/decimal.rst

@@ -103,7 +103,7 @@ reset them before monitoring a calculation.
 .. seealso::
 
    * IBM's General Decimal Arithmetic Specification, `The General Decimal Arithmetic
-     Specification <http://www2.hursley.ibm.com/decimal/decarith.html>`_.
+     Specification <http://speleotrove.com/decimal/decarith.html>`_.
 
    * IEEE standard 854-1987, `Unofficial IEEE 854 Text
      <http://754r.ucbtest.org/standards/854.pdf>`_.

Lib/decimal.py

@@ -17,7 +17,7 @@
 This is an implementation of decimal floating point arithmetic based on
 the General Decimal Arithmetic Specification:
 
-    www2.hursley.ibm.com/decimal/decarith.html
+    http://speleotrove.com/decimal/decarith.html
 
 and IEEE standard 854-1987:
 
@@ -130,6 +130,8 @@ __all__ = [
     'setcontext', 'getcontext', 'localcontext'
 ]
 
+__version__ = '1.70'    # Highest version of the spec this complies with
+
 import copy as _copy
 import math as _math
 import numbers as _numbers