Task query optional parameters (#69)

* Change TaskQuery struct parameters to optional

* Thrift API is modified to make all the parameters in the
  TaskQuery struct optional

* Autogenerated code is regenerated

* Changes in TaskQuery structs used in the project

* Now that TaskQuery receive optional values, pointers
  instead of values must be passed to the struct

realis_e2e_test.go

@@ -75,11 +75,7 @@ func TestNonExistentEndpoint(t *testing.T) {
 	)
 	defer r.Close()
 
-	taskQ := &aurora.TaskQuery{
-		Role:        "no",
-		Environment: "task",
-		JobName:     "here",
-	}
+	taskQ := &aurora.TaskQuery{}
 
 	_, err = r.GetTasksWithoutConfigs(taskQ)