In coding: cookies, use utf-8 rather than UTF-8, so Emacs is happy.
tools/builtin-py.py: mbcs may also create an ImportError.
README.org: New name and format for README.
Text revised to contain more relevant information.
index.html: Redirect to GitHub.  Recodec is not worth its own site.
builtin.py, recodec.html: Derived files, updated.