Message2859

I'm pretty hesitant to add a system property to specify something in Jython that has a corresponding mechanism in Python.  We'll be adding source file encodings per PEP 263 in the next version of Jython.  I realize this has the advantage that it makes all files UTF-8 or whatever encoding you choose by default, but that's balanced in my mind by the fact that code written like that won't work with CPython out of the box.  Does this patch have anything else to recommend it over PEP 263?