[Cin] Slightly updated russian translation

I asked my russian-speaking friend to check it, but this may take some time... Please *do not merge* this version yet - new bugs may surface as we try to look at messages Attached modified .po file and compiled .mo file too. I used few first steps from HOW-TO.TXT 1) cd <path>/cinelerra-x.x.x 2) run xgettext: ./po/xlat.sh > po/cin.po then I moved cin.po and ru.po from /dev/shm/tmp/cinelerra-goodguy-20200711/cinelerra-5.1/po into my working directory /home/guest/Cin-translations after this I used msgmerge --output-file=ru-3.po ru-2.po ru.po msgmerge --output-file=ru-4.po ru-3.po cin.po msgfmt -c -o ru.mo.new-4 ru-4.po So many steps because I wanted to have backups in case I mismerge something ...