Add NoiseEffect

[LucaArgentieri]

Related issue: #597

Description

• Removed ASCII effect demo (js duplicate)
• Noise effect implementation
• Created noise demo

[vanruesc]

Thanks for this. However, the old NoiseEffect from v6 is not very good and I'd prefer it if we could create a new and improved version for v7. The old one suffers from floating point overflow and pattern scaling artifacts.

It would be cool if the new NoiseEffect would support nice and stable noise patterns with well-defined animations and configuration options.

Unfortunately, I don't have enough time to help much with a new implementation.

Also, please keep in mind that PRs should be focused on the feature they aim to implement. Unrelated clean up commits should not be included (but thanks for pointing out that rogue .js demo 😅).

[vanruesc]

I've implemented a NoiseEffect with a more stable noise animation in 0be9718.

We can add more features to this later, like texture-based film grain.