Add new @map keyword to the coil parser.

In short it takes something like this:
a: {
    @map: [1 2 3]
    this: {
        foo: "this"
    }
    that: {
        foo: "that"
    }
    bar: ["a" "b" "c"]
}

and creates this:
a: {
    this1: {
        foo: "this"
        bar: "a"
    }
    this2: {
        foo: "this"
        bar: "b"
    }
    this3: {
        foo: "this"
        bar: "c"
    }
    that1: {
        foo: "that"
        bar: "a"
    }
    that2: {
        foo: "that"
        bar: "b"
    }
    that3: {
        foo: "that"
        bar: "c"
    }
}