Improve documentation

[clun]

When getting some help from the CLI responses are quite limited

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                            Version: 0.5

 - list commands       : astra help
️ - get command help    : astra help <your command>
️ - list your databases : astra db list
️ - create new database : astra db create demo

One may want to access web documentation, get support or see commands immediately:

New version: