fix issue #I3NU1A

增加流程运行时可以选择执行人或角色。包括流程审批、流程节点创建时，开始节点的下一个节点处理

OpenAuth.App/FlowInstance/Request/AddFlowInstanceReq.cs

@@ -15,7 +15,7 @@ namespace OpenAuth.App.Request
     /// <summary>
 	/// 创建工作流请求
 	/// </summary>
-    public class AddFlowInstanceReq 
+    public class AddFlowInstanceReq : NodeDesignateReq
     {
 
         /// <summary>

OpenAuth.App/FlowInstance/Request/NodeDesignateReq.cs

@@ -0,0 +1,20 @@
+using System.Collections.Generic;
+
+namespace OpenAuth.App.Request
+{
+    public class NodeDesignateReq
+    {
+        /// <summary>
+        /// 如果下个执行节点是运行时指定执行者。需要传指定的类型
+        /// <para>取值为RUNTIME_SPECIAL_ROLE、RUNTIME_SPECIAL_USER</para>
+        /// </summary>
+        public string NodeDesignateType { get; set; }
+        
+        /// <summary>
+        /// 如果下个执行节点是运行时指定执行者。该值表示具体的执行者
+        /// <para>如果NodeDesignateType为RUNTIME_SPECIAL_ROLE，则该值为指定的角色</para>
+        /// <para>如果NodeDesignateType为RUNTIME_SPECIAL_USER，则该值为指定的用户</para>
+        /// </summary>
+        public string[] NodeDesignates { get; set; }
+    }
+}

OpenAuth.App/FlowInstance/Request/VerificationReq.cs

@@ -1,6 +1,8 @@
-namespace OpenAuth.App.Request
+using System.Collections.Generic;
+
+namespace OpenAuth.App.Request
 {
-    public class VerificationReq
+    public class VerificationReq : NodeDesignateReq
     {
         public string FlowInstanceId { get; set; }
         /// <summary>
@@ -22,5 +24,6 @@
         /// 驳回类型。null:使用节点配置的驳回类型/0:前一步/1:第一步/2：指定节点，使用NodeRejectStep
         /// </summary>
         public string NodeRejectType { get; set; }
+        
     }
 }