Make vulkaninfo removal of promoted extension structures optional

[charles-lunarg]

PR #948 removed extension structures from vulkaninfo output that were promoted to core Vulkan, eg into the VkPhysicalDeviceVulkan(11|12|13)(Features|Properties) structs. It was done for Vulkan profile generation, but it users who are looking for the extension structures explicitly as they no longer appear.

PR 948 was a necessary contribution to allow correct Vulkan-Profile output, but should be a command line option, eg --remove-promoted-extensions --strip_duplicate_struct.

[christophe-lunarg]

In the Vulkan Profiles merge script, the argument is called --strip_duplicate_struct if we want to be consistant. If you prefer a different name, I'll happy to use that name.

(It's not promoted extensions, but the structures, even promoted structures, that are removed)

[charles-lunarg]

--strip_duplicate_struct is a much better name, because 'strip' better describes whats happening.