[product: zaphod][project: zaphod-v0.3]: [bug] Bad interaction between tests.

SYNOPSIS
[modified]m42/test/test_iputil.py: Don't set cmd_shell_function in setUp or tearDown.

DETAILS
The tests in a suite are run in an alphabetical fashion and setting
cmd_shell_function in setUp or tearDown is a bad idea. Instead
set it in the test_function itself and restore it in a finally clause.