Function debounce

debounce(delay: number, callback?: ConvertFunction): Transformer
Builds function which delays the synchronization for given msec.
Parameters
- delay: number
  time in msec to wait before synchronizing.
- Optionalcallback: ConvertFunction
  callback which transforms the value.
Returns Transformer
transformer function.
Example
```
let a = new Clazz({prop: 2});
let b = new Clazz();
Binding.for(a, b)
    .syncToRight("prop",
        debounce(100)
     ).enable().syncToRightNow();
b.prop // is undefined but will be set after 100msec to 2
```
- Defined in Transformers.ts:100