Added warning about ni's obsolescence. Retracted semantic changes

(i.e. when using ni, the old __init__.py semantics prevail!)

Doc/lib/libni.tex

@@ -2,6 +2,12 @@
 \label{module-ni}
 \bimodindex{ni}
 
+\strong{Warning: This module is obsolete.}  As of Python 1.5a4,
+package support (with different semantics for \code{__init__} and no
+support for \code{__domain__} or\code{f__}) is built in the
+interpreter.  The ni module is retained only for backward
+compatibility.
+
 The \code{ni} module defines a new importing scheme, which supports
 packages containing several Python modules.  To enable package
 support, execute \code{import ni} before importing any packages.  Importing

Doc/libni.tex

@@ -2,6 +2,12 @@
 \label{module-ni}
 \bimodindex{ni}
 
+\strong{Warning: This module is obsolete.}  As of Python 1.5a4,
+package support (with different semantics for \code{__init__} and no
+support for \code{__domain__} or\code{f__}) is built in the
+interpreter.  The ni module is retained only for backward
+compatibility.
+
 The \code{ni} module defines a new importing scheme, which supports
 packages containing several Python modules.  To enable package
 support, execute \code{import ni} before importing any packages.  Importing