Emit comments in the .js and .d.ts files

This enables adding comments to the .js and .d.ts for all the declarations when --removeComments is not specified
Note the comments aren't correctly formatted and have extra spacing when they are multiline comment. That is a todo I am fixing separately.
Also handling of copyright comments will be separate pull request
don't we want a space before the comment ? 
```TypeScript
/** class c1*/ class c1 {
}
/** class c2*/class c2 {
}
```

Becomes:
```javascript
/** class c1*/ var c1 = (function () {
    function c1() {
    }
    return c1;
})();
/** class c2*/ var c2 = (function () {
    function c2() {
    }
    return c2;
})();
```

Which is a good thing isn't it? We anyways format the code so this looks correct to me.