This commit fixes several issues in add-ons UI messages extraction code:
- In multi-file modules, the script would crash because it tried to write to
the dir instead of a `translations.py` file;
- The add-on message extraction works by enabling the add-on, getting all
messages; disabling the add-on, getting all messages; then comparing the
two message sets. But often a bug happens where a class gets a
description from somewhere else in memory. I couldn’t debug that, so a
workaround is to check that the message isn’t a corrupted one before
removing it;
- `printf()` doesn't exist in Python and would crash the script;
- `self.src[self.settings.PARSER_PY_ID]` can be replaced by `self.py_file`
in class `I18n`, since a property exists to do that;
- At one point a generator was printed instead of its values, so let's
unpack the generator to get the values. Maybe the print could be
deleted entirely;
- Use SPDX license identifier instead of GPL license block, to be more in
line with other scripts from the codebase.
Reviewed By: mont29
Differential Revision: https://developer.blender.org/D15474
c48dc61749