Added os specific example main entry point macros
Added os specific example main entry point macros

ming4883/Vulkan,grim210/Vulkan,SaschaWillems/Vulkan,SaschaWillems/Vulkan,dreadwords/Vulkan,ming4883/Vulkan,SaschaWillems/Vulkan,jpbruyere/Vulkan,SaschaWillems/Vulkan,jpbruyere/Vulkan,SaschaWillems/Vulkan,ming4883/Vulkan,martty/Vulkan,grim210/Vulkan