Update dependencies

[Pkoiralap]

I like this a lot; such a cool project.

I did a npm install and got

found 94 vulnerabilities (28 low, 22 moderate, 35 high, 9 critical) in 11201 scanned packages

I think this is because most of the packages being used are outdated.
May be improving on them is a good idea?

[t-book]

Hey @Pkoiralap, unfortunately, this client looks stale (as the community focused on mapstore2). If you like to jump updating the deps every contribution is welcome ;)