Some UI improvements

Changed the dark card background.
Added a background drawable which color changes when touched. This drawable is used for info buttons, checkboxes and on-demand checkboxes.

![Lists screenshots](https://cloud.githubusercontent.com/assets/3890441/4198219/70112b30-37f6-11e4-9792-4f721060feee.png)

Some paddings were changed to margins to make clickable areas square.

*There is a behavior that was here before: in the details list, when touching between the left arrow and the info button, the click is propagated to the parent which is then expanded / collapsed.*