Many interface improvements

I've spend few hours on this so this better be worth it ;)

Improvements:
- fonts sizes in various parts
- search interface (mainly POIs and lists)
- data management
- plugin manager

![screenshot_2013-07-12-02-47-19](https://f.cloud.github.com/assets/3075576/785759/a77fe14a-ea8d-11e2-8719-83e61b444f82.png)
![screenshot_2013-07-12-02-48-17](https://f.cloud.github.com/assets/3075576/785761/ab37eea4-ea8d-11e2-830e-37830f59a09f.png)
![screenshot_2013-07-12-02-48-46](https://f.cloud.github.com/assets/3075576/785762/ae4003d4-ea8d-11e2-9585-da86f8e975d7.png)
![screenshot_2013-07-12-02-49-51](https://f.cloud.github.com/assets/3075576/785764/b10065d2-ea8d-11e2-9037-9706838b7828.png)
![screenshot_2013-07-12-02-51-57](https://f.cloud.github.com/assets/3075576/785765/b414c894-ea8d-11e2-8c73-fc52f55b6bad.png)