New turret stats design and camera update

UI:

- Turret stats panel redesigned to fit more into the screen. Clicking on the Demolish button shows the confirmation dialog, so the user will not accidentally demolish a turret by clicking on the Confirm button right after the Demolish one.

- Laser turret's "disabled" image fixed. It was not visible previously.

Camera:

- Camera script has been rewritten.

1. When the mouse is close to the screen's edges, the Camera moves to that direction similarly to how WASD buttons move it.

2. Rotation, initialization fixed and now the Camera does not accidentally "jumps" or causes bugs when active window changes.