Dependencies review

[marco-brandizi]

We still have various issues with genomaps.js dependencies:

• npm audit still lists a number of vulnerabilities. While it's nearly impossible to eliminate all of them, we should makes as many update as possible.

• package.json lists dependencies that are never used via require(), so it's not clear if they are actually used or not, this should be cleaned. If there are dependencies that can't be explicitly included, at least add comments.

Note: we have to decide when to tackle this issue.