tools: moveconfig: allow to give CONFIG names as argument directly

We still pass the input file with CONFIG name, type, default value
in each line, but the last two fields are just ignored by the tool.
So, let's deprecate the input file and allow users to give CONFIG
names directly from the command line.  The types and default values
are automatically detected and handled nicely by the tool.

Going forward, we can use this tool more easily like:

  tools/moveconfig.py CONFIG_FOO CONFIG_BAR

Update the documentation and fix some typos I noticed while I was
working on.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>