Use the base name of the odd file to create the compiled version rather than the full path.

Previously:

    $ roma2 --compile long/path/to/somewhere.xml out

would create a compiled file at ``out/long/path/to/somewhere.xml.compiled``. The modification makes it so that the compiled file is at ``out/somewhere.xml.compiled``.

This is also fun:

    $ cd out
    $ roma2 --compile ../myTEI.xml .  # compiled version stored at ../myTEI.xml.compiled

I've not noticed a test suite. It would not hurt to inspect, run or test somehow this proposed modification before merging.