Add .com.apple.timemachine.donotpresent to OSX

.com.apple.timemachine.donotpresent is a system file created by TimeMachine on OSX by user choice.

Global/OSX.gitignore

@@ -15,6 +15,7 @@ Icon
 .TemporaryItems
 .Trashes
 .VolumeIcon.icns
+.com.apple.timemachine.donotpresent
 
 # Directories potentially created on remote AFP share
 .AppleDB