Madoko.net UI button to hide preview pane

[mattpalermo]

It is promising that Madoko.net seems to work somewhat on portable, small touch screens but there is not enough room to fit both the editor and preview pane. Usually the preview pane can be moved out of the way by dragging the center bar but this doesn't work with a touch screen. A button to maximize the editor pane just like the maximize preview pane button would help with this.