Provide an ability to redirect stdout and stderr

[MaxDesiatov]

carton test previously parsed output of tests that were run with wasmer. It's no longer possible to capture their output, I wonder if WAMR itself supports this at all?

[kateinoigakukun]

As far as I saw, WAMR doesn't provide a way to hook stdout/stderr 😢

One suggestion: How about launching another carton process in carton test, and execute Wasm binary with WAMR in the spawned process, then capture the output?

[MaxDesiatov]

In the meantime, I've created bytecodealliance/wasm-micro-runtime#482 to track this in WAMR proper.