Message3888

I've been working more on this to fix a few problems and clean it up a
bit. I would really like to see something along these lines integrated
into the mainline Jython code so that I don't have to keep patching the
sources every time a new release comes out. So if any of the maintainers
are interested in helping me check this in to the trunk, pls let me
know. I still have few questions about this, as well: for example, what
exactly the relationship between core/imp.java and module/imp.java
should be, and what to set __file__ to for module imports.

Finally, it would be nice to further extend this so that reading a file
from path __appletjar__/... using Python file I/O would magically try to
load the file from the applet jar. (I.e., make the same change for
read-only data as for code.)