#1 Allow command line use of Metatest

[Jonathan Fine]

As summary. Here's an example of what I'd like to do.

Python 2.4.1a0 (#2, Feb 9 2005, 12:50:04)
[GCC 3.3.5 (Debian 1:3.3.5-8)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from metatest.py.mymod import plus
>>> import metatest
>>> plus(2, 3) == 6
<MyStub 4>
>>> metatest.interactive = True # New command
>>> plus(2, 3) == 6
TestError: Expected '6', got '5'
>>>