Fixed Windows 8 input dialog

Fixed Windows 8 input dialog sliding out of the screen when keyboard is opened
Improved the looks of the input dialog

Before:
![input_old](https://cloud.githubusercontent.com/assets/431167/4892067/47049932-63ae-11e4-8eea-2f5ed33c2964.png)

After:
![screenshot_11032014_233912](https://cloud.githubusercontent.com/assets/431167/4892068/4d489a14-63ae-11e4-96c1-1119ca5d7803.png)