Add version_sort filter to properly sort list of versions (#1916)

* Add version_sort filter to properly sort list of versions

* Fix all comments from Felix

- add changelog fragment
- fix test by removing runme.sh/yml and renaming to filter_version_sort
- use fully qualified name of filter in test case

* Remove wrong plugin.test changelog fragment

Ups...

* Properly name the file version_sort.py

* Update changelogs/fragments/1916-add-version-sort-filter.yml

Co-authored-by: Felix Fontein <felix@fontein.de>

Co-authored-by: Eric L <ewl+git@lavar.de>
Co-authored-by: Felix Fontein <felix@fontein.de>

plugins/filter/version_sort.py

@@ -0,0 +1,21 @@
+# Copyright (C) 2021 Eric Lavarde <elavarde@redhat.com>
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+from distutils.version import LooseVersion
+
+
+def version_sort(value, reverse=False):
+    '''Sort a list according to loose versions so that e.g. 2.9 is smaller than 2.10'''
+    return sorted(value, key=LooseVersion, reverse=reverse)
+
+
+class FilterModule(object):
+    ''' Version sort filter '''
+
+    def filters(self):
+        return {
+            'version_sort': version_sort
+        }