added a get_content() method, which excludes command byte & term byte

chat_messages.hpp

@@ -33,6 +33,9 @@ namespace chat
 
         std::string get() const
         { return byte(_header) + _content + byte(message::TERM); }
+
+        std::string get_content() const
+        { return _content; }
     };
 
     std::ostream& operator<<(std::ostream& os, const chat_message& msg)