multiple version of node installation

* https://www.sitepoint.com/quick-tip-multiple-versions-node-nvm/
nvm ls-remote
nvm ls available (windows)

* see list of available node version in pc
nvm list

* install old version of node
nvm install 8.12.0

* Fortunately, when installing a new Node.js version, you can reinstall the npm global packages from a specific version. For example:

nvm install v9.0.0 --reinstall-packages-from=8.9

1)  nvm to manage node versions
2) npm for packages



nvm use latest
npm install -g ionic

nvm use 8.12.0
npm uninstall -g ionic
npm install -g ionic@3.9.2


For library adding
npm install --save

--save adds to package

nvm install 8.12.0 32 (32 bits)