Updated docs

  * big change in bin: now configuration file (rc) is located under
    ~/.rc;
  * removed some comments;
  * emacs/emacs.org: added variable to not include postamble into HTML,
    added variable to speedup tangling;
  * docs/scripts/cft2.org: tangle lua code to bin;
  * polytech/lua.org: removed from section local variables settings for
    export and tangling.

Signed-off-by: Vladimir Lomov <lomov.vl@gmail.com>