Request: Allow call signatures on classes

[rjamesnw]

Moving over request from here: https://typescript.codeplex.com/workitem/2464

Proposed Solution:

class A {
    [index: number]: A; // <- since you can already do this
    (...args): A; // <- why not allow this also?
    constructor(...args) { }
}

[RyanCavanaugh]

Duplicate of #183

[rjamesnw]

Sorry, I'm losing my mind. I think it open this request twice. :/ I did search first, not sure how I missed it. Working too late I guess. ;)