message: Expose `defaults` module in `iced_graphics`
  Fixes
diff: #![forbid(rust_2018_idioms)]
  #![cfg_attr(docsrs, feature(doc_cfg))]
  mod antialiasing;
  -mod defaults;
  mod primitive;
  mod renderer;
  mod transformation;
  @@ -17,6 +16,7 @@ mod viewport;
  mod widget;
  pub mod backend;
  +pub mod defaults;
  pub mod font;
  pub mod layer;
  pub mod triangle;
  