修正sdk好友和频道接口错误

common/src/main/java/cn/wildfirechat/pojos/OutputStringList.java

@@ -0,0 +1,22 @@
+package cn.wildfirechat.pojos;
+
+import java.util.List;
+
+public class OutputStringList {
+    private List<String> list;
+
+    public OutputStringList() {
+    }
+
+    public OutputStringList(List<String> list) {
+        this.list = list;
+    }
+
+    public List<String> getList() {
+        return list;
+    }
+
+    public void setList(List<String> list) {
+        this.list = list;
+    }
+}