* Bump API patch number and header version number to 44 for this update.
Github Issues:
* Fix description of <<features-extentperimagetype, Allowed Extent Values
Based On Image Type>> (public issue 290).
* Better specify VK_DEVICE_LOST behavior around flink:vkQueueSubmit,
flink:vkWaitForFences, and flink:vkGetFenceStatus (public issue 423).
* Clarify definition of flink:vkGetQueryPoolResults::pname:queryCount
(public issue 441).
* Simplify and clean up normative language. Remove shall and replace
recommend and variants with should wherever possible (public issue 448).
* Fix all dangling internal cross-references in the 1.0-extensions
specification, and add scripts/checkXrefs to find these in the future
(public issue 456).
* Reverse order of ChangeLog.txt entries so the most recent version is
documented first (public issue 463)
* Removes "become invalid" which clashes with invalid state for command
buffers. (public issue 467)
* Disallowed pending state in spec text for vkResetCommandBuffer, matching
valid usage (public issue 468)
* Removes sentence describing invalid state "like initial state". (public
issue 469)
* Disallows begin command buffer from resetting command buffers in the
"recording" state. (public issue 470)
* Removes mention of state from description of
VK_COMMAND_POOL_CREATE_RESET_COMMAND_BUFFER_BIT (public issue 471)
* Removed extra valid usage statement in VkSubmitInfo (public issue 472)
Internal Issues:
* Clarify description of the pname:imageLayout member of
sname:VkDescriptorImageInfo.
* Fix typos where etext:VK_VIEW_TYPE* was used instead of
etext:VK_IMAGE_VIEW_TYPE.
* Removed the <<VK_KHR_display>> and <<VK_KHR_display_swapchain>> example
code from the specification and noted it has been moved to the Vulkan
SDK cube demo (internal issue 179).
* Reorder VkExternalMemoryHandleTypeFlagBitsNV description (internal issue
480).
* Clarify than an implementation is
<<fundamentals-validusage-flags,permitted to return 'undefined' bit
flags>> in a bitfield (internal issue 640).
* Break Valid Usage statements describing unrelated parameters into
separate statements, and add a style guide entry to follow this approach
(internal issue 685).
* Move valid usage statement for slink:VkImageCreateInfo from spec body to
the explicit valid usage block (internal issue 693).
* Fix typos in the descriptions of slink:VkDisplaySurfaceCreateInfoKHR,
flink:vkCreateDisplayModeKHR, and
flink:vkGetDisplayPlaneSupportedDisplaysKHR in the <<display,Presenting
Directly to Display Devices>> section (internal issue 698, 704, 716).
* Clarified that mandatory depth/stencil formats are only a requirement
for 2D images (internal issue 719).
* Clarify that variables decorated with DeviceIndex/ViewIndex must be in
the Input storage class (internal issue 733).
* Work around generator script problem with removal of Unicode literals
from Python 3.0-3.2 using `future` package (internal issue 737).
* Remove nonexistent structure type enums from vk.xml (internal issue
738).
* Fix validextensionstructs attributes for structures in the pname:pNext
chain for VkPresentInfoKHR, fixing implicit valid usage statements for
those structures (internal issue 740).
New Extensions: