Feature Request: Variable Number of Arguments

_This issue was originally filed by ador...@gmail.com_

---

It would be nice to have variable numbers of arguments, a la python splats.

This would make porting python code to dart much cleaner.

For example, I would like to do something like this:

```dart
void myFunc(arg1, arg2, *anyRemainingArgs){
var extraArg1 = anyRemainingArgs[0];
var extraArg2 = anyRemainingArgs[1];
...
}
```

Start by reading the issue discussion and the Dart language specification context for function arguments. Determine the syntax and semantics required for Python-style variable arguments, including how remaining arguments are represented; done means the language-design questions are resolved and the accepted behavior is captured in the specification.

Written by the indexing model from the issue text.