Update strings.xml

https://github.com/MIUICzech-Slovak/MA-XML-5.0-SLOVAK/commit/38b04b0f6ed9f4083fdfd393f4ff66fef10b4f5b
![screenshot_2014-04-01-04-26-38](https://cloud.githubusercontent.com/assets/812995/2607967/f464cc7a-bb64-11e3-945f-4d0c71a0a7c0.png)