Feature: Support for left handed users

[finnboeger]

Allow toolbar to be moved to the right side to allow left handed users the use of WBO on touch devices without accidentally triggering the menu

[lovasoa]

Ideally, we should also be able to have the toolbar displayed horizontally at the top or the bottom of the screen. I already received negative feedbacks from an user with a small screen saying that the introduction of the new Circle and Grid tools made the toolbar too large for their browser window, pushing the last buttons below the bottom of the window and rendering them inaccessible.