The `'oneSide'` router is a restricted version of the `'orthogonal'` router. Exactly three route segments are generated. The route leaves the start element in a specified direction (the `args.side` property), transitions with a single segment towards the end element, and then enters the end element from the specified direction again. Note that this router does not support link `vertices`. The router does not avoid obstacles. Two arguments are accepted, which can be passed within the `router.args` property.

side | string | The direction of the route. Either `'left'`, `'right'`, `'top'` or `'bottom'`. Default is `'bottom'.`
padding | number | object | The minimum distance from element at which the first/last route angle may be placed. Default is `40`. The `util.normalizeSides` function is used to understand the provided value. A single number is applied as padding to all sides of the elements. An object may be provided to specify values for `left`, `top`, `right`, `bottom`, `horizontal` and/or `vertical` sides. Only the side specified in the `side` argument is considered by the router (see above).

Example:

    link.router('oneSide', {
        side: 'top',
        padding: 30
    });