Help message for wasm-pack build is not updated

[ibaryshnikov]

🐛 Bug description

In help message target still defaults to browser

More details:
wasm-pack build --help prints this:

-t, --target <target>        Sets the target environment. [possible values: browser, nodejs, web, no-modules]
                                 [default: browser]

In the book the default is bundler

Actually, both are supported, but --target browser silently became deprecated
https://github.com/rustwasm/wasm-pack/blob/master/src/command/build.rs#L97

🤔 Expected Behavior

wasm-pack build --help should print that bundler is the default target, and maybe include some information about deprecation of browser target

🌍 Your environment

wasm-pack version: 0.8.1

I'd like to submit a pr if this update makes sense

[ashleygwilliams]

ah ha! i did Not Realize that that had changed in wasm-bindgen. thank you so much for filing an issue. i'd love a PR for this and it would be great to also update the documentation!

cc @alexcrichton is this assessment correct? is there anything else that we may have missed that updated in wasm-bindgen? @ibaryshnikov please go ahead an open up a PR and we can discuss anything else there!

[alexcrichton]

Oh I think this is just outdated documentation, AFAIK the default is "bundler" in both wasm-bindgen and wasm-pack

[ashleygwilliams]

closed by #640 by way of #678