[LyX/master] Update Russian localization

[Juergen Spitzmueller]

commit 761648b1f7d1df9de87921143b8004b6d3dd21e9
Author: Yuriy Skalko <yuriy.skalko at gmail.com>
Date:   Wed Aug 26 10:23:28 2020 +0300

    Update Russian localization

 lib/doc/ru/UserGuide.lyx | 1393 ++++++++++++++++++++++++++--------------------
 po/ru.po                 |  144 +++---
 2 files changed, 860 insertions(+), 677 deletions(-)