Updated docs/emacs and docs/polytech

  * emacs.org: added several new templates, new option
    'cdlatex-paired-parens';
    - updated 'cdlatex-us.el';
  * scripts.org: small improvement: get rid of redundant '\\', use 'echo
    -e' to pass new lines to generated LTX file, use substitutions to
    make this works with LaTeX syntax.

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