* Update release number to 74.
Github Issues:
* Clarify which buffer locations are accessed in
flink:vkCmdCopyBufferToImage valid usage statements (public issue 676).
* Refine description of <<extended-functionality-extensions-dependencies,
extension dependencies>>, related NOTE in the
<<extended-functionality-extensions, Extensions>> section, and
"`Required Extensions`" glossary term (public pull request 693).
* Add support for specifying required Vulkan core version in `vk.xml` and
the extension metadoc generator (public issue 696).
* Update .gitignore for directory reorganization (public pull request
699).
* Fix typo (public pull request 703).
Internal Issues:
* Update valid usage of slink:VkClearRect::pname:layerCount (internal
issue 1241).
Other Issues:
* Fix typo in <<NV_geometry_shader_passthrough>> issues list.
associated material at the top level, vk.xml and associated material in
xml/, and generated include and source files in include/vulkan/ and
src/ext_loader/, respectively (public issue 436).
Jon Leech