Move dependency from node/npm to nvm

[nymous]

Using nvm would allow us to install any version of node, not depending on the target package manager (which can be outdated), and even multiple versions of node in parallel.
It also allows us to fix a node version using a .nvmrc file.
Finally, it allows installation of global packages without any specific configuration for any user, not requiring the use of sudo.

We would need to update the install scripts (Utils/scripts/).