More than 2 segments of a parameter

[ben-gillott]

It would be useful to support up to three parts of a function parameter, for example

void Test(out float varName){ }

[Checkmate50]

I think we should specifically add the ability to add "modifiers" to variables, which also includes things like uniform, attribute, in, intout, etc..., since these modifiers show up a decent amount in Graphics. I propose in particular that any modifier can be declared as valid with the syntax: declare modifier attribute, for example