Idea for "main" function syntax

[frame-lang]

Adding a main to a spec would enable compiled command line programs and easier testing scenarios.

fn main {
    #Test($(1,2), >(3,4), #(5,6))
}

#Test[$[a,b], >[c,d], #[e,f]]

    -machine-

    $S0 [a,b]
        |>| [c,d] print(a + b + c + d + e + f) ^


    -actions-

    print [msg] {
        ```
        print(msg)
        ```
    }

    -domain-

    var e = 0
    var f = 0

##