ready for merge in master (#964)

uevent should be format

Enum of smoltcp socket should be optimized.

need to add interface for routing subsys

actix is still not abled to run.

clean some casual added code to other places

user/apps/test_unix_stream_socket/README.md

@@ -0,0 +1,5 @@
+# unix stream socket 测试程序
+
+## 测试思路
+
+跨线程通信，一个线程作为服务端监听一个测试文件，另一个线程作为客户端连接监听的文件。若连接成功，测试能够正常通信。