Translated: 5.1 & 5.5
ru-RU: chapter 06 translated
Minor fixes and updates
Fixed misspelling 'preferencs > preferences'
ru-RU: chapter 07 translated
Merge branch 'master' of https://github.com/alexander-naumov/debian-handbook-ru
Merge branch 'master' of https://github.com/m-ka/debian-handbook-ru