Add an --emit-clif option to wasmtime compile

[elliottt]

Add the --emit-clif <PATH> option to wasmtime compile, making it easier to inspect the intermediate clif produced when compiling a wasm module. The path argument is a directory that will be created if its missing, and it will be populated with files named wasm_func_<idx>.clif, where <idx> is the function index in the wasm module.

Currently this option is only supported when using cranelift to compile a wasm module, and an error will be raised if winch is used instead.

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Label Messager: wasmtime:config

It looks like you are changing Wasmtime's configuration options. Make sure to
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[itsrainy]

This looks good to me! Just a couple small comments.

[itsrainy]

Looks like the build is failing because the Path import will only be included if built with features=wasmtime/cache

[elliottt]

Looks like the build is failing because the Path import will only be included if built with features=wasmtime/cache

Doh, thanks Rainy!