Deleting rexec.py and Bastion.py

[Guido van Rossum]

There have been reports of serious security problems with rexec.py and
Bastion.py starting with Python 2.2. We do not have the resources to
fix these problems. Therefore, I will disable these modules in the next
2.3 alpha release and in the next 2.2 release (2.2.3, no release date
scheduled). If you are using rexec.py or Bastion.py with any version
of Python 2.2 or 2.3 to safeguard anonymously submitted source code, I
strongly recommend that you stop doing so immediately, because it is
*not* safe.

There are also known security problems with older versions of Python,
but the holes created by Python 2.2 are much bigger (big enough to
drive an airplane carrier through).

--Guido van Rossum (home page: http://www.python.org/~guido/)