Huge engine change, replace all std::shared_ptrs

Create a new shared pointer type stdext::shared_object_ptr and stdext::shared_obj
using boost::intrusive_ptr

Advantages:
 * half memory usage
 * faster and lightweight

Disadvantages:
 * using weak_ptr is not supported anymore
 * compiling seems slower

src/framework/stdext/stdext.h

@@ -32,5 +32,6 @@
 #include "string.h"
 #include "dumper.h"
 #include "time.h"
+#include "shared_object.h"
 
 #endif