[Enhancement] Add Filters to Two.js

[jonobr1]

Is your feature request related to a problem? Please describe.
Both SVG and Canvas APIs have the ability to filter the rendering style of the content displayed. Take those along with custom shaders for the WebGL renderer to incorporate filtering into Two.js.

Describe the solution you'd like

var group = two.makeGroup();
group.add(circle, star, rectangle, path);
group.filter = 'blur(10px)';
star.filter = 'contrast(175%)'

Additional context
Filter specifications on MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/filter

[perminder-17]

Hi @jonobr1, I am Perminder singh, maintainer of p5.js. Interested in working on this issue. Can you assign this to me?

[jonobr1]

Thanks for diving in! Feel free to ask any follow up questions here. I think the SVG and Canvas implementation should be fairly straightforward, but there are a few different ways to approach this in WebGL

[jonobr1]

Referencing: #773