package includes development artifacts

[amphro]

Running npm install csvtojson will install the package with a lot of development artifacts.

The .ts-node is particularly causing problems for use because it is blowing out file path lengths on windows within our CLI.

This could be resolved with just doing a files property in the package.json. Are those shipped for any specific reason?

[joeyleshatwork]

This is also open as an issue here: https://github.com/Keyang/node-csvtojson/issues/387