Updated release date to match boilerplate.tex.

Removed implied future availability of an info/texi version of the other
manuals (the word "yet").

Guido, you might want to check this file to see if any other changes are
required.
diff --git a/Doc/texipre.dat b/Doc/texipre.dat
index 4f12e65..1f5778a 100644
--- a/Doc/texipre.dat
+++ b/Doc/texipre.dat
@@ -12,7 +12,7 @@
 knowledge about the Python language.  For an informal introduction to
 the language, see the Python Tutorial.  The Python Reference Manual
 gives a more formal definition of the language.  (These manuals are not
-yet available in INFO or Texinfo format.)
+available in INFO or Texinfo format.)
 
 Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
 The Netherlands.
@@ -91,7 +91,7 @@
 Reference Manual} gives a more formal definition of the language.
 (These manuals are not yet available in INFO or Texinfo format.)
 
-This version corresponds to Python version 1.5 (Oct 25 1996).
+This version corresponds to Python version 1.5 (Dec 31 1997).
 
 @end ifinfo