title: Error testing a method that throws an Error in Quick with Nimble
body: <p>I'm having a problem getting a Nimble matcher correct in testing a method that throws an exception.  According to the docs it should be simple.  I just need an expectation like this </p>
  
  <pre><code>expect( try somethingThatThrows() ).toNot( throwError() ) 
  </code></pre>
  
  <p>However with Swift 3 and Xcode 8.2 I'm getting a compiler editor.  Here's the context. </p>
  
  <pre><code>describe("Using RealmDatasource") {
  
     let datastore = RealmDatasource() as Datasource
  
         it("can retrieve an object") {
  
             expect( try datastore.getCurrentObject() ).to( throwError() )
  
         }
  
  }
  </code></pre>
  
  <p>I get the following error on the 'it' declaration line </p>
  
  <blockquote>
  <pre><code>Invalid conversion from throwing function of type '() -&gt; () throws to non-throwing function of type '() -&gt; ()'
  </code></pre>
  </blockquote>