Support FNM and NVM default installations

[ruromero]

What did you have in mind?

In order to provide better support for Javascript projects we should allow using Fast Node Manager (FNM) or Node Version Manager (NVM) with the default configuration.

Are you trying to fix a problem?

Most Javascript users rely on NVM or FNM for installing the package manager binaries

Any lead on how this feature can be implemented?

We can read the default environment variables for their installation (FNM_DIR or NVM_DIR) and use them when running the npm, yarn, pnpm binaries.

[ruromero]

Fixes fabric8-analytics/fabric8-analytics-vscode-extension#745