Remove rexec howto; it's kind of pointless now

Doc/howto/rexec.tex

-\documentclass{howto}
-
-\title{Restricted Execution HOWTO}
-
-\release{2.1}
-
-\author{A.M. Kuchling}
-\authoraddress{\email{amk@amk.ca}}
-
-\begin{document}
-
-\maketitle
-
-\begin{abstract}
-\noindent
-
-Python 2.2.2 and earlier provided a \module{rexec} module running
-untrusted code.  However, it's never been exhaustively audited for
-security and it hasn't been updated to take into account recent
-changes to Python such as new-style classes. Therefore, the
-\module{rexec} module should not be trusted.  To discourage use of 
-\module{rexec}, this HOWTO has been withdrawn.
-
-The \module{rexec} and \module{Bastion} modules have been disabled in
-the Python CVS tree, both on the trunk (which will eventually become
-Python 2.3alpha2 and later 2.3final) and on the release22-maint branch
-(which will become Python 2.2.3, if someone ever volunteers to issue
-2.2.3).
-
-For discussion of the problems with \module{rexec}, see the python-dev
-threads starting at the following URLs:
-\url{http://mail.python.org/pipermail/python-dev/2002-December/031160.html},
-and
-\url{http://mail.python.org/pipermail/python-dev/2003-January/031848.html}.
-
-\end{abstract}
-
-
-\section{Version History}
-
-Sep. 12, 1998: Minor revisions and added the reference to the Janus
-project.
-
-Feb. 26, 1998: First version.  Suggestions are welcome.
-
-Mar. 16, 1998: Made some revisions suggested by Jeff Rush.  Some minor
-changes and clarifications, and a sizable section on exceptions added.
-
-Oct. 4, 2000: Checked with Python 2.0.  Minor rewrites and fixes made.
-Version number increased to 2.0.
-
-Dec. 17, 2002: Withdrawn.
-
-Jan. 8, 2003: Mention that \module{rexec} will be disabled in Python 2.3,
-and added links to relevant python-dev threads.
-
-\end{document}
-
-
-
-