message::version is a member function (API Change):

fix #778

* The version data member is replaced with accessor
  member functions.

Actions Required:

* Call member function message::version instead of accessing
  the version member at call sites.

test/beast/websocket/rfc6455.cpp

@@ -24,9 +24,9 @@ public:
     test_is_upgrade()
     {
         http::header<true> req;
-        req.version = 10;
+        req.version(10);
         BEAST_EXPECT(! is_upgrade(req));
-        req.version = 11;
+        req.version(11);
         req.method(http::verb::post);
         req.target("/");
         BEAST_EXPECT(! is_upgrade(req));