Adding eslint and lint configuration to TypeScript SDK

[pcoet]

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@robertwb @kerrydc

Added eslint and TypeScript linting config to the TypeScript SDK. You can run it with npm run lint, but it's not integrated with the build step, so won't fail the build -- just informational. There are currently 4000+ problems, but a lot of them are low-hanging fruit: unused values, implicity any, or async declarations that don't await anything. I'd like to tidy up some...

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Can one of the admins verify this patch?

[asf-ci]

Can one of the admins verify this patch?

[robertwb]

Thanks for doing this. Would definitely welcome the code getting cleaned up!