Creating spectra

[lpatiny]

Here are just couple of ideas in order to improve spectra-data and planned the future ... It will be inspired a little bit from the project https://github.com/image-js/core

I will create many tickets in order to be able to discuss the points separately

Creating spectra

Loading spectra should return a Promise and probably accepts the following methods:

SD.fromJcamp (url or data)
SD.fromBruker (url to a zip or zipped file)
SD.fromXY ?
SD.from?? something compatible with the result of

Promise are required especially when we load the data from an URL