Drive ParticleSystem with an animation instead

Drive ParticleSystem with an animation instead

This will be helpful later, and also keeps the work in the main thread.

Change-Id: Idf4b9e82a40f31a0b70edda731b85b6c853a1dac
Reviewed-on: http://codereview.qt.nokia.com/1909
Reviewed-by: Alan Alpert <alan.alpert@nokia.com>
Reviewed-by: Martin Jones <martin.jones@nokia.com>