Change `.nmrium` internal format

[lpatiny]

This is a huge work of migration to file-collection in which we move out the spectra from the data.json files (we only keep reference to the original data).

This will be very close to the NMReData format.

https://github.com/cheminfo/file-collection

[jobo322]

Currently, our NMReData reader uses Filecollection.

So at the level of nmr-load-save a zipped .nmrium file could contain the data (like bruker folders, jcamp-dx) and each spectrum would contain in sourceSelector the property files with the relative path. It is the way to read the data, is it correct @lpatiny ?