Adds extensive integration tests that exercise the various ways of finding
the Vulkan-Headers.
vk-bootstrap should now use the Vulkan-Headers or Vulkan::Headers targets if
they were already defined (such as is the case of FetchContent), and will
look for the VulkanHeaders package and Vulkan package as a fallback, and will
FetchContent Vulkan-Headers directly if that fails.
This should make integration seamless with the various ways vulkan-headers
is acquired.
The vk-bootstrap-vulkan-headers target was dropped in favor of directly
linking to Vulkan-Headers (creating a target by that name if none exists).
VulkanSC was added to vk.xml and broke the generation script. This was an
easy fix, just needed to specify which API the version information should
use. Still, took the time to cleanup the code by running pylint and fixing
anything it warned about.
find_package is used to try to find the Vulkan-Headers, and if they aren't
present, it downloads them with fetch content. This way users don't need
vulkan 'installed' on their system, specifically for windows users.
It also changes the tests to load all the necessary function pointers, that
way we don't need to find the vulkan loader to build the tests.
Added device::get_queue_families() to facilitate custom queue setups
get_swapchain_images() renamed to get_image(), made member function to
swapchain.
get_swapchain_image_views() renamed to get_image_views(), also moved to
member function of swapchain
fixed bug with headless instance not being correct
Stopped Catch2 from polluting the buildable targets
