Specifies the speed of animation.
A String value. The default is 'normal', stating that animation will run at relatively normal speed.
The following values are acceptable:
- 'veryfast' - slides are changed very fast
- 'fast' - slides are changed faster than normal
- 'normal' - slides are changed at relatively normal speed
- 'slow' - slides are changed slower than normal
- 'veryslow' - slides are changed very slowly
Supported in: v1.0.