Add WASM build target for Web version of glslang

This adds build rules to support generating a WASM binary to be used
on the web. The API exposed to web applications is definated in the
new glslang.js.cpp file.

Add in header for uint32_t definition

This is needed for stricter/newer MSVC builds of downstream users.

Convert no RTTI rule to be compiler specific

MSVC uses a different flag for disabling RTTI, so is currently
including RTTI information and throwing warnings.

Automapping opengl location

Handle SPIR-V type mismatch when constructing a composite

Fix bug in printing trailing comma when dumping AST for a structure.

Sync code from KhronosGroup/glslang.

Remove execute permission from LICENSE.txt

This reverts commit 50ada66c, reversing
changes made to 3464b6f5.

Automapping opengl location

Fix missing decoration and bug in member remap

control shaders.
Fix bug in member remapping.

Update spirv-tools and spirv-headers known good.

Previous known-good contained regression per sperron at Google.

Update known good SPIRV-Tools commit

Update the known good SPIRV-Tools commit to eventually propagate the
commit allowing the ray tracing stages in pass instrumentation to the
vulkan validation layers (validation layers depends on glslang which
depends on spirv-tools).

ESSL: Fix #1823: Conditions for when derivatives are in compute shader.

Fix #1818: Allow unsized view array dimension for non-block perviewNV attributes

SPV: Fix #1783: Don't do bounds checking for spec-const-expression size

OpIsHelperInvocationEXT should declare relevant SPV extension and capability