Updating Russian
Merge pull request #549 from gaich/patch-3

Updating Russian. Thanks to gaich @ XDA
added changelog
Fixed #550
Fixed #550
Fixed #557
Updated Czech translation

Minor fixes to existing strings.
Updates to match
https://github.com/asksven/BetterBatteryStats/issues/550 and
https://github.com/asksven/BetterBatteryStats/issues/557