Setup page for first time usage

[canack]

Gama can be downloaded by package managers. Because of this, users might find it difficult to use if they are not familiar with the instructions on the GitHub page.

When Gama is first run, if there is no default configuration or if the --setup parameter is not passed, it offers the user an interactive setup opportunity.

[canack]

Just forwarding GitHub page to read instructions is enough I think. I can handle that basically on information pane.