Add UAV (image) binding offset and HLSL register class support

SPV: The execution scope for barriers should be Workgroup.

SPV: Fix unreferenced variable warning with AMD_EXTENSIONS disabled.

HLSL: allow promotion from 1-vector types to scalars, e.g, float<-float1

Previously, an error was thrown when assigning a float1 to a scalar float,
or similar for other basic types.  This allows that.

Also, this allows calling functions accepting scalars with float1 params,
so for example sin(float1) will work.  This is a minor change in
HlslParseContext::findFunction().

HLSL: Allow expressions in attributes

For example:

[numthreads(2+2, 2*3, (1+FOO)*BAR)]

This will result in a thread count (4, 6, 8).

Rationalizes the entire tracking of the linker object nodes, effecting
GLSL, HLSL, and SPIR-V, to allow tracked objects to be fully edited before
their type snapshot for linker objects.

Should only effect things when the rest of the AST contained no reference to
the symbol, because normal AST nodes were not stale. Also will only effect such
objects when their types were edited.

This PR adds:

1. The "u" register class for RW* objects.

2. --shift-image-bindings (== --sib), analogous to --shift-texture-bindings etc.

3. Case insensitive reg classes.

4. Tests for above.

Fix build warnings in iomapper.cpp, re-indent to glslang standard

This has no functional changes.

HLSL: implement numthreads for compute shaders

HLSL -> Spir-V: Resource mapping handler

HLSL: Add min*{float,int,uint} types

Use std::atoi instead of std::stoi

Some Android cross cross-compilers don't have std::stoi.

E.g. i686-linux-android-g++ from Android NDK r10e don't have std::stoi.

These HLSL types are guaranteed to have at least the given number of bits, but may have more.

min{16,10}float is mapped to EbtFloat at medium precision -> SPIRV RelaxedPrecision
min{16,12}int and min16uint are mapped to mediump -> SPIR-V RelaxedPrecision

This PR adds handling of the numthreads attribute for compute shaders, as well as a general
infrastructure for returning attribute values from acceptAttributes, which may be needed in other
cases, e.g, unroll(x), or merely to know if some attribute without params was given.

A map of enum values from TAttributeType to TIntermAggregate nodes is built and returned.  It
can be queried with operator[] on the map.  In the future there may be a need to also handle
strings (e.g, for patchconstantfunc), and those can be easily added into the class if needed.

New test is in hlsl.numthreads.comp.

Add explicit lambda return types, for compilers without C++14 support

- add optional callback to handle mapping of uniform variables in linking phase
- if no resolver is provided, it uses the internal default resolver with all shifts and auto bind settings

Change-Id: Icfe38a9eabe8bfc8f8bb6d8150c06f7ed38bb762

silence -Wunknown-pragmas warnings on gcc

HLSL: allow component-wise operations for logical || and &&.

HLSL: Enable component-wise vector comparisons from operators

GLSL: apply unused variable

HLSL || and && can operate component-wise.

This PR only changes a few lines of code, but is subtle.

In HLSL, comparison operators (<,>,<=,>=,==,!=) operate component-wise
when given a vector operand.  If a whole vector equality or inequality is
desired, then all() or any() can be used on the resulting bool vector.

This PR enables this change.  Existing shape conversion is used when
one of the two arguments is a vector and one is a scalar.

Some existing HLSL tests had assumed == and != meant vector-wise
instead of component-wise comparisons.  These tests have been changed
to add an explicit any() or all() to the test source.  This verifably
does not change the final SPIR-V binary relative to the old behavior
for == and !=.  The AST does change for the (now explicit, formerly
implicit) any() and all().  Also, a few tests changes where they
previously had the return type wrong, e.g, from a vec < vec comparison
in hlsl.shapeConv.frag.

Promotion of comparison opcodes to vector forms
(EOpEqual->EOpVectorEqual) is handled in promoteBinary(), as is setting
the proper vector type of the result.

EOpVectorEqual and EOpVectorNotEqual are now accepted as either
aggregate or binary nodes, similar to how the other operators are
handled.  Partial support already existed for this: it has been
fleshed out in the printing functions in intermOut.cpp.

There is an existing defect around shape conversion with 1-vectors, but
that is orthogonal to this PR and not addressed by it.

Disabled MSVC 2015 compile warnings.

I happened upon numArgs while hunting for unused variables. I suspect
the intent was to apply it as shown in this patch. However, I am not a
compiler dude. Someone more appropriate should grok this change.

HLSL: fix defect in EOpMethodSampleCmp* texture decomposition

HLSL: phase 4 of RWTexture support: add image atomics

HLSL: Fix unary and binary operator type conversion issues

SPV: Add missing guard to code that uses AMD extensions