cmds.distro: Move all modules to lib

Functions abstracting the distribution are not only needed in the
context of the distro subcommand, but also by other code, so make the
bulk of the code abstracting the distribution available in some place
more universally useful than below cmds.distro.

This commit leaves the source files mostly unchanged. They are only
patched to fix import paths, so that functionality is preserved.
Refactoring the code from command-line API to library API will be
done by the next commit.

Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/lib/distros/debian/Select.py

@@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+
+from typing import Iterable
+from argparse import Namespace
+
+from ...Package import Package
+from ...pm.dpkg import query_packages
+from ...Cmd import Cmd
+from ..BeSelect import BeSelect as Base
+
+class Select(Base):
+
+    def __init__(self, parent: Cmd):
+        super().__init__(parent)
+
+    async def _all_installed_packages(self) -> Iterable[Package]:
+        return await query_packages()