Project WASM compatibility first step

[pedrovgs]

This PR is the first step to be able to make the project compatible with WASM. We here provide some fallback implementations and disable some complex functions and features but make build usabe on WASM.

My next iteration will focus on the features I had to disable to be able to use this project with Swift WASM.

[pedrovgs]

@kateinoigakukun do you happen to know why the CI build is failing in this PR? I can see it passing locally 🤔

I guess it's a memory issue, but don't know if this is on the toolchain side or our side.

[pacowong]

Thanks. I mainly trust the test results and check some functions as it is impossible to review all functions in a short time.

[pedrovgs]

Thanks for the review @pacowong I've just added one last commit fixing CI for WASM that was broken only on CI because of the usage of an unstable version. Yuta confirmed the version we have to use and CI should be passing now 😃