horizontal layout

[wiiznokes]

related to #31, but more up to date.

fixes #22

todo:

• refractor the view code to reuse some part on both branch
• text field should not take the full width
• content should be scrollable
• content should take full height
• left and right arrow should focus the next one only in pano layout
• entry should have a max and min width
• make horizontal option in settings popup

and

• not enable by default