Updated emacs

  * emacs: removed comments added meta-comment;
  * auctex-us.el: changed LaTeX-math-abbrev-prefix to `F9' and add
    CDLaTeX into AUCTeX,
  * org-us.el: added CDLaTeX integration and some useful settings for it
    (have to write function);
  * keybinds-us.el: removed '<TAB>' binding (bad interact with CDLaTeX),
    removed gnuplot binding (not using at all).

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