Check if CLI is installed via NPM

[alansemenov]

Before we can publish CLI on NPM, we need to correctly communicate to the user info about the latest available version and instructions on upgrade.

To check latest version of the CLI on NPM:
npm view @enonic/cli version

To check if CLI was installed with NPM:
npm list -g @enonic/cli

If not installed, it will return

/Users/ase/.npm-global/lib
└── (empty)

If installed, it will return something like

/Users/ase/.npm-global/lib
└── @enonic/cli@2.3.4 -> ./../../dev/cli-enonic

The version here (2.3.4) should be parsed (note that it can potentially end with -Bx or -RCx) and verified with the latest version available on NPM (see the first command above). If it's lower, we should suggest upgrade:

Latest available version is 2.3.5. Run 'npm upgrade @enonic/cli' to update CLI

Only if CLI is NOT installed from NPM, should we proceed to the current version check we have now and suggest upgrade via Brew or Scoop.