#5734 Fix convert-ly with Python 3

[Jonas Hahnfeld]

Fix convert-ly with Python 3

The error was "'str' object has no attribute 'decode'", so it already
is decoded. The encoding seems to also be correct, as filenames with
Unicode characters work just fine.
It's worrying that none of the usual testing commands seem to invoke
the script with a real input file, only the output of --help is used.

---

If possible I'd like to push this as soon as possible. The normal process
fails on convert-ly anyhow...

http://codereview.appspot.com/555260044

[Jonas Hahnfeld]

Drop line

http://codereview.appspot.com/555260044

[Anonymous]

Passes make, make check and a full make doc.

[Anonymous]

Patch on countdown for Feb 8th.

[Jonas Hahnfeld]

Skipping countdown - as David correctly notices:

from "doesn't work" there cannot be much more of a regression to be afraid of.

commit e76d6918c3c5704de3ed90c58340cd804f79439e
Author:     Jonas Hahnfeld <hahnjo@hahnjo.de>
AuthorDate: Tue Feb 4 19:58:06 2020 +0100
Commit:     Jonas Hahnfeld <hahnjo@hahnjo.de>
CommitDate: Thu Feb 6 12:03:34 2020 +0100

    Issue 5734: Fix convert-ly with Python 3

    The error was "'str' object has no attribute 'decode'", so it already
    is decoded. The encoding seems to also be correct, as filenames with
    Unicode characters work just fine.
    It's worrying that none of the usual testing commands seem to invoke
    the script with a real input file, only the output of --help is used.