Updated docs

  * emacs/emacs.org: added basic configuration for dired;
  * openbox/rc.org: removed almost unused keybinds;
  * scripts/misc.org: removed (actually moved to subtree tagged as
    :obsolete:noexport:) script 'dir-open' because it is almost unused.

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