Provide results of parent tasks when action is run

[pcj]

It would be nice to support the following:

task("namer", [], function() {
   return "world!";
});

task("greet", ["namer"], function(named: any) {
   console.log("Hello,", named);
});

So, the return value of a parent task is provided to the task.action() function, in the order it appears in the deps array.