fpm experiment 8

[amitu]

Rust has a string "hello". Rust calls hello_wasm() defined in wasm with the string as the input. hello_wasm() adds " yo wasm" to the string. Then wasm calls rust's function hello_host()with the modified string.hello_host()` appends " yo from host" to the string and returns it back to wasm. Wasm then appends, "wasm says yo again" to it, and returns it to the original rust code, which then prints it on console.

In the process all allocated memory should be cleanly cleaned as soon as we are done with the memory.