implement 1.9.17 new api - setTestCaseTestSuite

[lczub]

TL future release 1.9.17 delivers a new api setTestCaseTestSuite

related TL Mantis Task

• 7875: [API - XMLRPC] new method setTestCaseTestSuite (fman)
• 7802: [API - XMLRPC] Need an API to move test case between test suites (fman)

   /**
    * 
    * @param struct $args
    * @param string $args["devKey"]
    * @param string $args["testcaseexternalid"] format PREFIX-NUMBER
    * @param int    $args["testsuiteid"] 
    * 
    */
  public function setTestCaseTestSuite($args)
  {