Rework stdext classes

Implement new classes:
* stdext::any => ligher replacement for boost::any
* stdext::packed_any => like any but optimized to use less memory
* stdext::shared_object => ligher replacement for std::shared_ptr
* stdext::shared_object_ptr => replacement for boost::intrusive_ptr
* stdext::fast_storage => for storing dynamic data
* stdext::packed_storage => same but with less memory
* stdext::packed_vector => std::vector with less memory

Compiling should be a little faster now because global boost including
is not needed anymore

src/framework/net/connection.h

@@ -62,7 +62,7 @@ public:
     bool isConnecting() { return m_connecting; }
     bool isConnected() { return m_connected; }
 
-    ConnectionPtr asConnection() { return self_cast<Connection>(); }
+    ConnectionPtr asConnection() { return static_self_cast<Connection>(); }
 protected:
     void onConnect(const boost::system::error_code& error);
     void onWrite(const boost::system::error_code& error, size_t);