issue #1 添加分组管理接口-创建分组接口

src/main/java/chanjarster/weixin/api/WxServiceImpl.java

@@ -4,6 +4,7 @@ import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.security.MessageDigest;
+import java.text.MessageFormat;
 import java.util.Arrays;
 import java.util.UUID;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -18,6 +19,7 @@ import org.apache.http.impl.client.HttpClients;
 
 import chanjarster.weixin.bean.WxAccessToken;
 import chanjarster.weixin.bean.WxCustomMessage;
+import chanjarster.weixin.bean.WxGroup;
 import chanjarster.weixin.bean.WxMassGroupMessage;
 import chanjarster.weixin.bean.WxMassNews;
 import chanjarster.weixin.bean.WxMassOpenIdsMessage;
@@ -183,6 +185,12 @@ public class WxServiceImpl implements WxService {
     return WxMassSendResult.fromJson(responseContent);
   }
   
+  public WxGroup groupCreate(String name) throws WxErrorException {
+    String url = "https://api.weixin.qq.com/cgi-bin/groups/create";
+    String responseContent = execute(new SimplePostRequestExecutor(), url, MessageFormat.format("'{'\"group\":'{'\"name\":\"{0}\"}}", name));
+    return WxGroup.fromJson(responseContent);
+  }
+  
   /**
    * 向微信端发送请求，在这里执行的策略是当发生access_token过期时才去刷新，然后重新执行请求，而不是全局定时请求
    * @param executor