Working on dereference function. Function convert_cy_ret_to_py is reused in dereference function, so I also modify some parts of that function, so it now can be used for dereferencing. In pyobjus_type.pxi added ObjcInt and ObjcFloat types, which are needed for dereference function, because user need to say pyobjus in which type to convert void pointer. Other types also will be added (ObjcLong, ObjcUnsignedInt, etc.)