Feature request: Port over nvm's "default global packages"

[dcousineau-godaddy]

nvm has a feature that I would find useful in my current developer setup. The specific feature is default global packages that are installed on every new version of node setup.

Our development environment at my current job relies on a few globally-installed npm packages and it can be a headache to remember to install them when jumping to a new node version, or jumping to an older version that has been previously cleared.