Bug 1836152

Description of problem:
The version shipped in RHEL 8 is 2.0.4, and because of the Python 3 switch it uses Python 3 instead of Python 2. The problem is that itstool 2.0.4 had a number of issues with Python 3, and those make itstool unusable in certain situations.

For example:

  $ git clone https://github.com/itstool/itstool git
  $ cd git
  git$ mkdir tmp
  git$ itstool -n -o tmp/test.pot tests/LocaleFilter/Locale1Xml.xml
  git$ stat --format '%s' tmp/test.pot
  0

Bug #1 I ran into.

  git$ itstool -n tests/LocaleFilter/Locale1Xml.xml > tmp/test.pot

Workaround for issue #1 above.

  git$ stat --format '%s' tmp/test.pot
  697
  git$ msgfmt -o tmp/fr_FR.mo tests/LocaleFilter/Locale1Xml.fr_FR.po
  git$ itstool -n -o tmp/test.xml -j tests/LocaleFilter/Locale1Xml.xml tmp/*.mo
  Error: Could not merge translations:
  'NoneType' object has no attribute 'split'

Bug #2 I ran into.

  git$ stat --format '%s' tmp/test.xml
  0

And there are more about this, e.g. with the -o option in various modes [2]. I hit issue #1 when trying to use itstool in another project, osinfo-db [3].

Looking at the log of the upstream repository between 2.0.4 and 2.0.6 shows that basically almost all the fixes are related to Python 2 vs 3 compatibility, and still there are open issues [1] about that.
This is why I'm asking for a rebase instead of reporting the issues: backporting all the Python 3 fixes would be more work than simply rebase to the latest upstream release (2.0.6); also, the current fix-segfaults.patch patch can be dropped.

[1] https://github.com/itstool/itstool/issues/35
[3] https://github.com/itstool/itstool/issues/28
[2] https://gitlab.com/libosinfo/osinfo-db/-/merge_requests/133