title: How to write several scope names in karate feature?
body: <p>Karate version: 0.6.0 Java version: 1.8
  I've put scope names (needed for token generation) in a json file.</p>
  
  <pre><code>{"scopeFoo": "foo",
    "scopeBar": "bar",
    "scopeRead": "read",
    "scopeWrite": write}
  </code></pre>
  
  <p>In karate feature I would like to have</p>
  
  <pre><code>* def sc = read(scopes.json)    
  * form field scope = "foo bar read write"
  </code></pre>
  
  <p>When I do:</p>
  
  <pre><code>* def sc = read(scopes.json) 
  * form field scope = sc.scopeFoo + sc.scopeBar + sc.scopeRead + sc.scopeWrite
  </code></pre>
  
  <p>It doesn't work. Even without spaces: </p>
  
  <pre><code>* form field scope = sc.scopeFoo+sc.scopeBar+sc.scopeRead+sc.scopeWrite
  </code></pre>
  
  <p>What is wrong? Thanks
  I can access scopes.json file in my feature, because with one scope it works</p>