Overlays a string of text over the image.

Valid options:

- color         Text Color (hex number)
- shadowColor   Color of the shadow (hex number)
- hAlign        Horizontal alignment: left, center, right
- vAlign        Vertical alignment: top, middle, bottom
- hOffset
- vOffset
- fontPath
- fontSize
- shadowOffset

@param string $text
@param array  $options

@return $this