setup.py: Specify encoding when reading README.rst
setup.py: Specify encoding when reading README.rst

https://github.com/clearlinux-pkgs/python-kconfiglib adds a patch for
this.

It avoids issues on systems that use the C locale, which implies ASCII
encoding and raises UnicodeDecodeError when reading README.rst.

Piggyback adding 'menuconfig' as another keyword.

ulfalizer/Kconfiglib,ulfalizer/Kconfiglib