Multi-file sketches

Last week, I posted that you can now use external Javascript libraries when creating sketches in the public studios (studio.sketchpad.cc and p5js.sketchpad.cc.) I extended this functionality to support another popular request: you can now create multi-file sketches by load code from one Sketchpad sketch into another Sketchpad sketch. This means, among other things, that you can better organize your code into files that can be edited independently, you can reuse classes across multiple sketches, and you can even make use of classes built by others people on Sketchpad.