MINOR: hlua_fcn: add Server.is_dynamic()

This function returns true if the current server is dynamic,
meaning that it was instantiated at runtime (ie: from the cli)
diff --git a/doc/lua-api/index.rst b/doc/lua-api/index.rst
index deef261..5c05871 100644
--- a/doc/lua-api/index.rst
+++ b/doc/lua-api/index.rst
@@ -1166,6 +1166,14 @@
    server.
   :returns: a boolean
 
+.. js:function:: Server.is_dynamic(sv)
+
+  Return true if the server was instantiated at runtime (e.g.: from the cli)
+
+  :param class_server sv: A :ref:`server_class` which indicates the manipulated
+   server.
+  :returns: a boolean
+
 .. js:function:: Server.set_maxconn(sv, weight)
 
   Dynamically change the maximum connections of the server. See the management
diff --git a/src/hlua_fcn.c b/src/hlua_fcn.c
index dc9ded4..61eb580 100644
--- a/src/hlua_fcn.c
+++ b/src/hlua_fcn.c
@@ -1086,6 +1086,20 @@
 	return 1;
 }
 
+int hlua_server_is_dynamic(lua_State *L)
+{
+	struct server *srv;
+
+	srv = hlua_check_server(L, 1);
+	if (srv == NULL) {
+		lua_pushnil(L);
+		return 1;
+	}
+
+	lua_pushboolean(L, (srv->flags & SRV_F_DYNAMIC));
+	return 1;
+}
+
 int hlua_server_set_maxconn(lua_State *L)
 {
 	struct server *srv;
@@ -1437,6 +1451,7 @@
 	hlua_class_function(L, "get_rid", hlua_server_get_rid);
 	hlua_class_function(L, "is_draining", hlua_server_is_draining);
 	hlua_class_function(L, "is_backup", hlua_server_is_backup);
+	hlua_class_function(L, "is_dynamic", hlua_server_is_dynamic);
 	hlua_class_function(L, "set_maxconn", hlua_server_set_maxconn);
 	hlua_class_function(L, "get_maxconn", hlua_server_get_maxconn);
 	hlua_class_function(L, "set_weight", hlua_server_set_weight);