Update README.md

[atherdon]

Is your feature request related to a problem? Please describe.

src # Folder with static JSON files. WTF what is going on here

Describe the solution you'd like
this comment is an actuall example that we need to add more context to what and why working as we set it up #363 (comment)

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A clear and concise description of any alternative solutions or features you've considered.

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[atherdon]

for me is not clear how to run build from readme. i think this section should be more advanced: https://github.com/GroceriStar/sd#npm-commands

[atherdon]

Readme -> explanation, related to module resolver + add alias, related to tests