title: What's the difference between ko.utils.unwrapObservable and ko.toJS?
body: <p>What are the differences between the 2?</p>
  
  <p>Surely they are the same thing since an unwrapped observable strips down to a js primitive. So why have ko.toJS or vice-versa?</p>
  
  <p>Also, why is there a ko.mapping.toJS?  Does this not effectively do the same as ko.toJS?
  There seems several functions in knockoutJS which do the same thing but there must be a reason why they exist.</p>