cmds.CmdPosix: Add command

Add a new group of commands - "posix". The current command categories are not a good fit for that: "projects" is for CI, "distro" is distribution-specific for CD, and secrets is for handling secrets specifically. Introduce the more general command group "posix", a class of commands not POSIX compliant in the exposed API, but primarily using POSIX utilities as workhorse.
Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/cmds/CmdPosix.py

@@ -0,0 +1,15 @@
+# -*- coding: utf-8 -*-
+
+from argparse import ArgumentParser
+
+from ..App import App
+from .Cmd import Cmd as CmdBase
+
+class CmdPosix(CmdBase): # export
+
+    def __init__(self, parent: App) -> None:
+        super().__init__(parent, 'posix', help='Perform various operations on a distro through its POSIX utility interface')
+        self._add_subcommands()
+
+    def add_arguments(self, p: ArgumentParser) -> None:
+        super().add_arguments(p)