* Update to rust 1.60.0
* Rename the feature `convert_bytemuck` to `bytemuck`
* Rename the feature `serialize` to `serde`.
* Make use of the "weak dependency" cargo feature
* Set rust-version = "1.60" for all crates
* egui_glow: clipboard, links, persistence & winit are now opt-in features
* egui_web: use tracing crate
* egui_glow: use tracing crate
* Log at the debug level
* egui_demo_app: enable tracing to log to stdout
* Use tracing in egui-winit
* Add opt-in tracing support to egui
* Switch to using glow as the default renderer both on native and the web
* Simplify code to find WebGL context for glow
* egui_web: make webgl an opt-in feature
* Stop using deprecated WEBGL_debug_renderer_info
* Move window building to egui-winit
* Move icon loading to egui-winit
* `use glow::HasContext;` -> `use glow::HasContext as _;`
* Move FileStorage into epi behind a feature flag
* De-duplicate screen_size_in_pixels and native_pixels_per_point
* Move creation of FileStorage to epi
* Handle epi app output (window size changes etc) in egui-winit
* Move app and memory persistence and autosave logic to egui-winit
* fix check.sh
* Make the epi backend opt-in for egui_glium and egui_glow
* Fix persistence
* Add integration name to epi::IntegrationInfo and the demo
* Clean up Cargo.toml files and fix making egui_glium optional
* fix typo
* Make egui_glium compile without the `epi` feature
I've extracted all the http request code and turned it
into its own crate at <https://github.com/emilk/ehttp>.
There was never a reason for the HTTP request library to be part of
`eframe`. Much better to have it as its own crate!
* Use old 1.51 toolchain instead of bleeding edge
1.52 and 1.53 has problems with incremental compilation,
so some people chose to stay on 1.51 for now.
So let's make sure egui supports 1.51 for a while!
* Update to cint 0.2.2 to get rust 1.51.0 compatability
* Deny doc errors
* Add intentional bad intradoc link to test CI
* Add cargo doc to CI
* Fix carg doc web (add wasm32 target)
* Fix intentionally broken doc-link
