* Update release number to 76.
Internal Issues:
* Add an exception clause to the license on `vk.xml`, enabling its use
with GPL-based projects (internal issue 1017).
* Remove the generated `vulkan_ext.[ch]` files, which are no longer
supported. Add `src/ext_loader/README.md` explaining why, and update
files in `xml/` to not generate them by default (internal issue 1268)
Other Issues:
* Fix typos in valid usage statements for the
ftext:vkDrawIndexedIndirectCount* commands, replacing
sizeof(VkDrawIndirectComment) with sizeof(VkDrawIndexedIndirectCommand).
* Modify the <<spirvenv-module-validation, Validation Rules within a
Module>> section to require code:NonReadable or code:NonWriteable in
SPIR-V code for images with an image format of code:Unknown if one of
the requisite code:shaderImageReadWithoutFormat or
code:shaderImageWriteWithoutFormat features is disabled.
New Extensions:
* `VK_KHR_get_display_properties2`
* `VK_KHR_draw_indirect_count`
Jon Leech