Created Unassigned: Make DrawablePath chainable [1384]

Make it possible to change:

```C#
image.Draw(new DrawablePath(
new PathMoveToAbs(75, 70),
new PathLineToAbs(90, 20),
new PathLineToAbs(105, 70)));
```
into:
```C#
image.Draw(new DrawablePath()
.MoveToAbs(75, 70)
.LineToAbs(90, 20)
.LineToAbs(105, 70)));
```