Changed the paint style of TextShape

Before this change, a `TextShape` was only capable of creating hollow (unfilled) text and rendering it to the screen. Setting the paint style in the `draw(Drawing)` method fixed this problem:

`paint.setStyle(Style.FILL);`

I think that, by default, a `TextShape` should be filled. A fillable toggle can allow the paint style in the `draw(Drawing)` method to be changed, permitting the creation of hollow or filled shapes by calling `setFilled(boolean)`. When writing Android applications using the Sofia API, I found myself often having to create a `FilledTextShape` class that extended `TextShape` to make this small change.