Feat/add sdk node example

[DanielZhangReal]

Add node.js version of SDK example

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[ferrell-code]

Sweet! But util.js probably would be useful for third party dev. They can't import it, maybe export it from sdk?

[DanielZhangReal]

Sweet! But util.js probably would be useful for third party dev. They can't import it, maybe export it from sdk?

You are right. But this utils is only for the node side. Later, the monorepo of the SDK will be considered. At that time, these utils can be considered to be added to a separate node package.
I am still planning about monorepo, but there will be some plans in the near future.