Added sorting by time in DB panel

The initial state:
![d2](https://f.cloud.github.com/assets/288535/2267099/1971b85e-9ead-11e3-8a7e-f3db84612e4e.png)

Sorting by time in descending order:
![d1](https://f.cloud.github.com/assets/288535/2267098/19710670-9ead-11e3-961f-3d632fb5afc3.png)