- Add missing constructor ops to support float16/int16/uint16 types
- Allow half float literals
- Correct two errors of double literal parse in HLSL: extension check and
  postfix

Fix memory leak upon ProcessDeferred failure.

Allow --hlsl-enable-16bit-types to be used without AMD_EXTENSIONS

Fixed GCC+Clang errors and warnings on Linux and OSX.

Merge branch 'fixup_sm_60_wording' of https://github.com/sheredom/glslang into sheredom-fixup_sm_60_wording

Now, version 5.* is all connected to making the uint type, which doesn't quite work.
Generator versions 4 and 6 do not do this.

SPV: Implement Vulkan 1.1 features and extensions.

This reverts commit 2c65069e, reversing
changes made to fa9b465b.

Legalization: Omit legalization warning when spirv-opt is linked.

Update spirv-tools known_good

Add more error checks for interpolateAtVertexAMD()

Still missing is automation and final decisions on mechanisms in general.

Implement the extension GL_AMD_gpu_shader_half_float_fetch

Fix issues of SPIRV headers

- Support new opaque types: f16sampler*, f16image*, f16subpassInput*.
- Add new built-in GLSL texture/image functions.