Fix compiling and add sample decoder

[nasirhemed]

Issues with Compiling

I was running into issues when trying to build on my local and realized that there were some issues.

typescript was complaining about type issues in node_modules/**/.d.ts files. To fix that, I upgraded to typescript 4.2.4

There were some this.document.<attr> that weren't referenced as (this.document as any).<attr> so typescript complained that document does not have 'attr'. I added as any to fix that issue.

Finally, tsconfig had some redundant config values so I just removed them.

Added Sample Decoder

I also added a sample_decoder to include inspect.js and inspect.wasm files

[tdaede]

This looks OK.

The sample decoders are technically build artifacts, I'm not necessarily opposed to including them in-tree but it would be good for them to be reproducible. At minimum I'd like a script and the exact libaom versions you used to generate them.

[nasirhemed]

I added a readme within sample decoder to add instructions on how to generate the artifacts. https://github.com/xiph/aomanalyzer/blob/ca6c82ac127e638d815c2223817f42b9f707b7e7/sample_decoder/readme.md

Introduced "typeRoots": ["./node_modules/@types"], to tsconfig.json as the node_modules of parent folder[awcy] was in conflict with analyzer

I also added this to tsconfig.json

[tdaede]

OK. I'm still not super hot on the idea of the .wasm/.js build artifacts being checked into git - I think they are nice thing to have but I don't really like committing build artifacts.

If you split those commits into a separate PR so we can discuss it further, we can land the other changes in this PR.

[nasirhemed]

Okay I'll remove the artifacts for this PR. I still think we need to have a way for the user to have access to inspect.js/inspect.wasm as there aren't instructions on how to get them and the emscripten build for aom is currently a bit messy.

I'll create a draft PR so that we can discuss this further