Create some Scrawl-canvas entitys which we can use with our Emitter entity
Create a particle Emitter entity
Check to see that the Emitter entity can lock to the mouse cursor
Check the effect of changing the world object's tickMultiplier (world speed) attribute
Check that particle color, and opacity appearance, can be controlled via the user-defined attributes in the world object (particle stroke color, minimum fill color, maximum fill color, opacity)
Check the effects of changing the following emitter/particle attributes: historyLength; generationRate
Confirm that particles comply with changes in the emitter's kill radius attributes
Check that the canvas backgroundColor attribute can be updated (background color)
Change the emitter's artefact; check that the update is immediate and impacts on all existing particles as well as new ones
Navigate away from the web page (open another tab in the browser) and, a few seconds later, navigate back to the page - check that the animation resets and starts, and does not freeze the page
