Update p5.strands docs to not use a uniform for time

[davepagurek]

Increasing access

Now that millis() works automatically in p5.strands, many animated shader examples in the reference will work without having to introduce the concept of uniforms to users, leaving that for more advanced usage, e.g. passing in the value of a slider or something like that.

Most appropriate sub-area of p5.js?

• Accessibility
• Color
• Core/Environment/Rendering
• Data
• DOM
• Events
• Image
• IO
• Math
• Typography
• Utilities
• WebGL
• Build process
• Unit testing
• Internationalization
• Friendly errors
• Other (specify if possible)

Feature enhancement details

There are examples in many (all?) of the build*Shader methods, e.g. https://beta.p5js.org/reference/p5/buildfiltershader/, all of which can be updated.

[nbogie]

I'd like to work on that - useful to have to review a bunch of examples.

[davepagurek]

Thanks @nbogie!

[nbogie]

(done)