add removeExtensions

[ousttrue]

• in order to prevent the platform-specific type is introduced

version(DVulkan_VK_NV_external_memory_win32) alias PFN_vkGetMemoryWin32HandleNV = VkResult function(VkDevice device,VkDeviceMemory memory,VkExternalMemoryHandleTypeFlagsNV handleType,HANDLE* pHandle);

• number suffixed extensions has no function and types, but only extension enum.

version(DVulkan_VK_KHR_extension_60) { enum VK_KHR_EXTENSION_60_SPEC_VERSION = 0; enum VK_KHR_EXTENSION_60_EXTENSION_NAME = "VK_KHR_extension_60"; }