Move tracking descriptor index to MVKDescriptorSetLayoutBinding from MVKDescriptorSetLayout.
Refactor MVKDescriptorSet::write() to be more DRY.
Grow and shrink MVKDescriptorSet memory consumption during allocate and free.
MVKPhysicalDevice refactor layout of pipelineCacheUUID to remove redundancy in MoltenVK
revision and allow tracking of enabled features that affect pipeline cache content.
MVKBitArray support resizing and simplify setBit() functionality.