[WIP] Lambda

[pjc0247]

Supprting a lambda expression has high priority on task queue.
Current status is partially implemented.

Below code works

list.Any((int x) => { return x > 2; });

And these are won't work

// implicit lambda parameter
list.Any((x) => { return x > 2; });

// lambda with arrow body
list.Any((int x) => x > 2);