macOS High Sierra compatibility

@el bingo > Pioneer DJ never tests with beta versions of operating systems as there have been changes made between the betas and official public releases in the past which broke PDJ software or drivers. It is only once the official public release is available that our teams begin testing the software and drivers for compatibility. We expect this process to be completed by the end of October and do not recommend any users upgrade at this time as we will not officially support High Sierra until such time. Thanks for your patience.