support wasm-sys console log coloring output

It would be cool for this library to somehow support (behind a toggle feature) colored output using `web-sys`'s [console::log()](https://rustwasm.github.io/wasm-bindgen/api/web_sys/console/fn.log.html) function's ability to output coloured/styled text. `log("%c text that is red %c text that is blue", "color: red", "color: blue")`, that way it can be used with wasm applications.