Add a page with short description of relevant projects

We should have a link to 'Building blocks' that presents couple of relevant projects with some download monthly statistics. Some of the numbers will be impressive !

Projects could be sorted using the following categories
- file parsing / generation
- jcampconverter, xy-parser, convert-to-jcamp, netcdf
- data-processing
- ir-spectrum, mass-tools, nmr-processing, openchemlib-js, ...
- machine learning
- ml-matrix, ml-pca, spectra-processing, ...
- image processing
- tiff, fast-png, image-js, mrz

There could be a link to npm and github. The number of download icon could be the link to npm.

We can add the number of download: https://img.shields.io/npm/dm/xy-parser?color=blue