Add teardown_role for correct TIME_WAIT behavior (API Change):

* teardown_tag is replaced with teardown_role, a client/server
  flag used to determine whether the shutdown is performed
  before or after reading the EOF. This is in accordance with
  RFC6455 7.1.1:

  https://tools.ietf.org/html/rfc6455#section-7.1.1

Actions Required:

* Modify signatures of teardown and async_teardown to use
  teardown_role instead of teardown_tag

* Change calls to teardown and async_teardown to pass the
  correct role: client or server depending on context.

test/extras/include/boost/beast/test/fail_stream.hpp

@@ -161,21 +161,24 @@ public:
 
     friend
     void
-    teardown(websocket::teardown_tag,
+    teardown(
+        websocket::role_type role,
         fail_stream<NextLayer>& stream,
-            boost::system::error_code& ec)
+        boost::system::error_code& ec)
     {
         if(stream.pfc_->fail(ec))
             return;
-        beast::websocket_helpers::call_teardown(stream.next_layer(), ec);
+        using beast::websocket::teardown;
+        teardown(role, stream.next_layer(), ec);
     }
 
     template<class TeardownHandler>
     friend
     void
-    async_teardown(websocket::teardown_tag,
+    async_teardown(
+        websocket::role_type role,
         fail_stream<NextLayer>& stream,
-            TeardownHandler&& handler)
+        TeardownHandler&& handler)
     {
         error_code ec;
         if(stream.pfc_->fail(ec))
@@ -184,8 +187,9 @@ public:
                 bind_handler(std::move(handler), ec));
             return;
         }
-        beast::websocket_helpers::call_async_teardown(
-            stream.next_layer(), std::forward<TeardownHandler>(handler));
+        using beast::websocket::async_teardown;
+        async_teardown(role, stream.next_layer(),
+            std::forward<TeardownHandler>(handler));
     }
 };
 

test/extras/include/boost/beast/test/pipe_stream.hpp

@@ -197,13 +197,15 @@ public:
 
         friend
         void
-        teardown(websocket::teardown_tag,
+        teardown(
+            websocket::role_type role,
             stream& s, boost::system::error_code& ec);
 
         template<class TeardownHandler>
         friend
         void
-        async_teardown(websocket::teardown_tag,
+        async_teardown(
+            websocket::role_type,
             stream& s, TeardownHandler&& handler);
     };
 
@@ -229,8 +231,10 @@ public:
 
 inline
 void
-teardown(websocket::teardown_tag,
-    pipe::stream& s, boost::system::error_code& ec)
+teardown(
+    websocket::role_type,
+    pipe::stream& s,
+    boost::system::error_code& ec)
 {
     if(s.fc_)
     {
@@ -247,7 +251,7 @@ teardown(websocket::teardown_tag,
 template<class TeardownHandler>
 inline
 void
-async_teardown(websocket::teardown_tag,
+async_teardown(websocket::role_type,
     pipe::stream& s, TeardownHandler&& handler)
 {
     error_code ec;

test/extras/include/boost/beast/test/stream.hpp

@@ -440,13 +440,13 @@ public:
 
     friend
     void
-    teardown(websocket::teardown_tag,
+    teardown(websocket::role_type,
         stream& s, boost::system::error_code& ec);
 
     template<class TeardownHandler>
     friend
     void
-    async_teardown(websocket::teardown_tag,
+    async_teardown(websocket::role_type role,
         stream& s, TeardownHandler&& handler);
 };
 
@@ -654,7 +654,7 @@ async_write_some(ConstBufferSequence const& buffers,
 
 inline
 void
-teardown(websocket::teardown_tag,
+teardown(websocket::role_type,
     stream& s, boost::system::error_code& ec)
 {
     if(s.in_.fc)
@@ -672,7 +672,7 @@ teardown(websocket::teardown_tag,
 template<class TeardownHandler>
 inline
 void
-async_teardown(websocket::teardown_tag,
+async_teardown(websocket::role_type,
     stream& s, TeardownHandler&& handler)
 {
     error_code ec;

test/extras/include/boost/beast/test/string_iostream.hpp

@@ -150,7 +150,7 @@ public:
 
     friend
     void
-    teardown(websocket::teardown_tag,
+    teardown(websocket::role_type,
         string_iostream&,
             boost::system::error_code& ec)
     {
@@ -160,7 +160,7 @@ public:
     template<class TeardownHandler>
     friend
     void
-    async_teardown(websocket::teardown_tag,
+    async_teardown(websocket::role_type,
         string_iostream& stream,
             TeardownHandler&& handler)
     {

test/extras/include/boost/beast/test/string_istream.hpp

@@ -138,7 +138,7 @@ public:
 
     friend
     void
-    teardown(websocket::teardown_tag,
+    teardown(websocket::role_type,
         string_istream&,
             boost::system::error_code& ec)
     {
@@ -148,7 +148,7 @@ public:
     template<class TeardownHandler>
     friend
     void
-    async_teardown(websocket::teardown_tag,
+    async_teardown(websocket::role_type,
         string_istream& stream,
             TeardownHandler&& handler)
     {

test/extras/include/boost/beast/test/string_ostream.hpp

@@ -126,7 +126,7 @@ public:
 
     friend
     void
-    teardown(websocket::teardown_tag,
+    teardown(websocket::role_type,
         string_ostream&,
             boost::system::error_code& ec)
     {
@@ -136,7 +136,7 @@ public:
     template<class TeardownHandler>
     friend
     void
-    async_teardown(websocket::teardown_tag,
+    async_teardown(websocket::role_type,
         string_ostream& stream,
             TeardownHandler&& handler)
     {