Handle function call arguments labels

[MikaelElkiaer]

The return label for a function should have all constants replaced with labels for the corresponding parameters. Formal parameters with explicit labels should be used directly, and the labels of the corresponding actual parameters should be at least as restrictive as those. Formal parameters with implicit labels should use the label of the corresponding actual parameter.

[MikaelElkiaer]

Create object for each function declaration, containing return label and formal parameters. For each formal parameter: name, label, and number.