Translation updates for 7.4/7.5: postgres-ru.po

Hello Peter,

Attached patch brings in new translations for 'postgres'
as well as fixes various typos and spelling errors
throughout the file. Please install for both 7.4 and 7.5.
(I'll keep maintaining it this way till about string freeze, maybe)

$ msgfmt -cvf postgres-ru.po
617 translated messages, 1200 untranslated messages.

Thanks,

-s

postgres-ru.po.gz