Thanks to `impl From<bool> for Vec2b` one can now shorten some builder
calls, like:
Previous:
```rust
egui::ScrollArea::vertical()
.auto_shrink([false; 2])
```
New:
```rust
egui::ScrollArea::vertical()
.auto_shrink(false)
```
* Update images in README.md
* Add ferris image to hello_world example
* Clean up and improve README.md, with top-level link to Rerun
* Move sections around
* Imoprove docs for callback shapes
* Improve docs for loader traits
* Use snake_case for feature `all_loaders`
* Make loaders publix
* Slightly better error message on image load failure
* Improve image loading error messages
* Use `bytes://` schema for included bytes loader
* Try user loaders first
* Move `image_loading_spinners` to `Visuals`
* Unify and simplify code
* Make the main text of `Button` optional
This largely makes ImageButton obsolete
* Fix docstrings
* Better docs
* typos
* Use the more explicit `egui_extras::install_image_loaders`
* Simplify `Image::paint_at` function
* add egui logo to widget gallery
* improve "no image loaders" error message
* rework static URIs to accept `Cow<'static>`
* remove `RetainedImage` from `http_app` in `egui_demo_app`
* hide `RetainedImage` from docs
* use `ui.image`/`Image` over `RawImage`
* remove last remanant of `RawImage`
* remove unused doc link
* add style option to disable image spinners
* use `Into<Image>` instead of `Into<ImageSource>` to allow configuring the underlying image
* propagate `image_options` through `ImageButton`
* calculate image size properly in `Button`
* properly calculate size in `ImageButton`
* Update crates/egui/src/widgets/image.rs
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* improve no image loaders error message
* add `size()` helper to `TexturePoll`
* try get size from poll in `Button`
* add `paint_at` to `Spinner`
* use `Spinner::paint_at` and hover on image button response
* `show_spinner` -> `show_loading_spinner`
* avoid `allocate_ui` in `Image` when painting spinner
* make icon smaller + remove old texture
* add `load_and_calculate_size` + expose `paint_image_at`
* update `egui_plot` to paint image in the right place
* Add helpers for painting an ImageSource directly
* Use max_size=INF as default
* Use new API in WidgetGallery
* Make egui_demo_app work by default
* Remove Option from scale
* Refactor ImageSize
* Fix docstring
* Small refactor
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
