[Help Needed] Implement error handling

[Roba1993]

What is this about

This PR is trying to support error handling within wasm-bindgen.
This is especially needed if a library is created with wasm-bindgen, which is then used in the browser as well as in a rust executable.

Related Issues & PRs

Following issues are related to this PR:

• Replace Result<T, JsValue> with Result<T, Error> #1742
• Create a JsError type #1017
• Allow for returning custom error type in Result #1004

There was already the PR #1173 which has addressed this issue.
At that time the PR has been closed, because failure::Error doesn't implement std::error::Error.
This problem should not exist anymore, because failure::Error is deprecated.

Support needed

I took the original implementation from #1173 and created this PR for it. @RReverser, I hope this is okay for you.
Unfortunately I don't understand wasm-bindgen enough to correctly handle the __wbindgen_error_new adapter.
This part of the source code has changed so much, that I need support to finish this implementation.

[RReverser]

@RReverser, I hope this is okay for you.

TBH I'd prefer if you cherry-picked the commit and made your modifications on top of it in follow-up commits - otherwise it loses authorship information.

[Roba1993]

@RReverser I can close this PR if you want, would you then create a new one? I didn't been able to pull that off in the right way :/

[RReverser]

@Roba1993 Nah, don't close it. What you can do is edit the commit message (via git commit --amend) to include extra Co-Authored-By: Ingvar Stepanyan <me@rreverser.com> line in the end - Github will recognise that too.