Merge changes I6e89439a,I9d9aafe6,I38340654,Ie50a9d37,Icd98abf5, ... into nyc-dev

* changes:
  vulkan: deprecate device layers
  vulkan: detect errors in VkEnumerate*ExtensionProperties
  vulkan: do not distinguish instance or device LayerRef
  vulkan: make Get*LayerRef take a Layer
  vulkan: refactor layer extension enumeration
  vulkan: refactor layer enumeration