Add option for automatically sharing a website

[oe3gwu]

OnionShare can automatically connect to the TOR Network. It also can Pin a website. But start sharing is a manual option. There should be an automatism for this too. At least on CLI level.

[mig5]

It sounds like a duplicate of #1574 , in terms of the UI.

In terms of the CLI, it makes no sense/already works: executing the CLI in website mode does start the share automatically, there is no in-between step. You pass --website and the path to the folder containing your HTML files/assets.