Common: CrossPlatform.hpp

The Cross Platform header located in the Common folder contains basic cross-platform headers that are used by several other source and header files. In the case any code requires the use of WinSock2.h, sys/socket.h, unistd.h, cstdint.h, ws2tcpip.h or windows.h, make sure to include this header instead of a direct include to any of this files. It is also required the usage of #if in the case of platform specific code (defines included with Platformident.hpp, also located on Common folder).