Translate modules

[JukkaL]

An Alore module with a single file (directory with a single file) should be translated to a file without a directory. Report a warning if overwriting a file.

An Alore module with multiple files should be translated into a directory with a suitably constructed __init__.py file.

For example:

m/x.alo => x.py

m/x.alo and m/y.alo => m/x.py, m/y.py and m/__init__.py, where
__init.py__ is like this:

from x import *
from y import *