Convert standard_kconfig() to argparse for better feedback

Stuff like this is not the pinnacle of helpful design, and hides that
the commands actually have long help texts (that can be viewed with
pydoc):

    $ ./menuconfig.py --help
    [Errno 2] No such file or directory: '--help'

Fix it by converting standard_kconfig() to argparse, and add a
'description' argument to it for the command-specific help text. --help
now shows the same help text shown by pydoc, and some other error
messages are improved as well.

Also fix some copy-paste errors and outdated paths in the help texts for
the all*config commands.

1 files changed, 3 insertions, 3 deletions

diff --git a/README.rst b/README.rst
index 4ff63e9..98049a3 100644
--- a/README.rst
+++ b/README.rst
@@ -280,12 +280,12 @@ For HTML output, add ``-w``:
 
 This will also work after installing Kconfiglib with ``pip(3)``.
 
-Documentation for the ``menuconfig`` and ``guiconfig`` interfaces can be viewed
-in the same way:
+Documentation for other modules can be viewed in the same way (though a plain
+``--help`` will work when they're run as executables):
 
 .. code:: sh
 
-    $ pydoc3 menuconfig/guiconfig
+    $ pydoc(3) menuconfig/guiconfig/...
 
 A good starting point for learning the library is to read the module docstring
 (which you could also just read directly at the beginning of `kconfiglib.py