Implement HTTP client test

Fix #479

src/main/scala/com/github/shadowsocks/utils/CloseUtils.scala

@@ -0,0 +1,35 @@
+package com.github.shadowsocks.utils
+
+/**
+  * @author Mygod
+  */
+object CloseUtils {
+  type Disconnectable = {
+    def disconnect()
+  }
+
+  def autoClose[A <: AutoCloseable, B](x: => A)(block: A => B): B = {
+    var a: Option[A] = None
+    try {
+      a = Some(x)
+      block(a.get)
+    } finally if (a.nonEmpty) try {
+      val v = a.get
+      if (v ne null) v.close
+    } catch {
+      case ignore: Exception =>
+    }
+  }
+  def autoDisconnect[A <: Disconnectable, B](x: => A)(block: A => B): B = {
+    var a: Option[A] = None
+    try {
+      a = Some(x)
+      block(a.get)
+    } finally if (a.nonEmpty) try {
+      val v = a.get
+      if (v ne null) v.disconnect
+    } catch {
+      case ignore: Exception =>
+    }
+  }
+}