Replace tracing with log (#2928)

* Replace tracing crate with log

It's just so much simpler to use

* Add `bacon wasm` job

* eframe: add a WebLogger for piping log events to the web console

crates/egui_extras/src/lib.rs

@@ -28,13 +28,13 @@ pub use crate::sizing::Size;
 pub use crate::strip::*;
 pub use crate::table::*;
 
-/// Log an error with either `tracing` or `eprintln`
+/// Log an error with either `log` or `eprintln`
 macro_rules! log_err {
     ($fmt: literal, $($arg: tt)*) => {{
-        #[cfg(feature = "tracing")]
-        tracing::error!($fmt, $($arg)*);
+        #[cfg(feature = "log")]
+        log::error!($fmt, $($arg)*);
 
-        #[cfg(not(feature = "tracing"))]
+        #[cfg(not(feature = "log"))]
         eprintln!(
             concat!("egui_extras: ", $fmt), $($arg)*
         );