--noUnusedParameters does not work good enough

**TypeScript Version:**  2.0.0

**Code**

``` ts
function fn(p1: any, p2: any): void {
  return p2;
}
```

**Expected behavior:**
This should compile even with --noUnusedParameters

**Actual behavior:** 
Fails when p1 is unused.

Since this is method signature and callside may not be possible to fix this, the compiler should only flag unused from the end.
