Fixes to my old icons and some new icons

I've colored system-leave icons, again, but i think thet fits theme. Gray icons looks bad on many plasma themes in shutdown dialogs, and they (just my opinion) never were used in one place with other actions.
![situation3](https://cloud.githubusercontent.com/assets/2522130/3030506/cba1b6ac-e041-11e3-8aaa-bfbb24e717ec.png)
Qt icons backgound i have fix, but i left old(original) text logo. May be Qt3-like(www.cs.huji.ac.il/~osdmitryp/img/Qt-logo.gif) would be better.
If something is wrong, i can fix and reopen pull request