Update russian translation

[Blueberryy]

Fixes and improvements

[alanedwardes]

Thank you for the contribution - I have now merged this PR. I did remove one change though - you had the following:

#. Key:	CheckboxDisableSubtitles
#. SourceLocation:	/Game/Resources/Localisation/ST_Menus.ST_Menus
#: /Game/Resources/Localisation/ST_Menus.ST_Menus
msgctxt "Menus,CheckboxDisableSubtitles"
msgid "Disable Subtitles"
msgstr "Отключить субтитры"

#. Key:	CheckboxEnableClosedCaptions
#. SourceLocation:	/Game/Resources/Localisation/ST_Menus.ST_Menus
#: /Game/Resources/Localisation/ST_Menus.ST_Menus
msgctxt "Menus,CheckboxEnableClosedCaptions"
msgid "Enable Closed Captions"
msgstr "Включить субтитры"

I believe you have translated the above to "Disable Subtitles" and "Enable Subtitles". But that's not quite right, "Enable Closed Captions" isn't the same as "Enable Subtitles" -- closed captions is the audio description portion of the subtitle system, e.g. things like "[loud bang]", "[crash]", whereas subtitles is dialogue. So I reverted that translation back to what it was ("Включить скрытые субтитры").