Normalize package.json files, to prepare publication on NPM

[Kocal]

Q	A
Bug fix?	no
New feature?	no
Issues	Fix #...
License	MIT

This is a first iteration for #2575: rework our package.json files in order to make them more "friendly" and work on npm.

Next steps:

1. Add some verifications, to ensure PHP and JS versions of a same package are identical (and so 100% compatible)
2. See how we can deploy JS packages when creating a new UX releases. I'm thinking about a full automated process using the CI with a workflow listening on tag creation, which will be responsible to upgrade the version from package.json files, commit, push, and publish to npm)
3. Check if we need to manually create the packages on npm before trying to publishing them