Updated docs/scripts and docs/gmrun

  * scripts, gmrun: changed name of auxiliary script, 'calc-eval' ->
    'calc-it', first name is already used by Emacs eshell (that I use
    too), updated gmrun config file accordingly;
    - bin/calc-eval -> bin/calc-it;
    - gmrun/gmrunrc: refresh, tangled from Org document.

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