Fix all the usage of Bytes type to really mean bytes.
Have logic in the SPIR-V front-end to detect the comparison properties of samplers and images.

- Includes test

Until now the WGSL parser would interpret a character index as a byte index.
This could lead to a panic on invalid input strings like "\"\u{2}ПЀ\u{0}\"",
because it would use that index to slice a string without ensuring the slicing
happens on a character boundary.

One possible fix would have been to call `str::find` instead of `position`,
however by relying on `splitn` instead of slicing a str manually it is
easier to convince ourselves that this code can no longer panic.

Fixes https://github.com/gfx-rs/naga/issues/90

- Require 4.1 as 4.0 now gives compile errors

* Add initial pomelo glsl work

* Fix ref to glsl_old

* Fix idents with numbers in lexer

* Use glsl_new for .vert in convert example

Controlled by PREFER_GLSL_NEW=1 env var

Also add simple test files

* Start making parser look like spec

* Port 'old' lex.rs to glsl_new

* Apply fixes after rebasing

* Fix clippy issue

* Fix PR comments

- Make into optional feature glsl-new

- Minor code style improvements

* Add test for `glsl_phong_lighting`

* Implement `ReturnValue` op for SPIR-V backend

Add Physical Layout test

Add Instruction tests

Add Logical Layout test

* Add glsl handling to convert sample

- Also fis extension check for spv and wgsl (missing .)

* Use std::path::Path for ext handling

* Also fix ext for .comp

Missing from last commit

* Basic glsl support

* Miscellaneous fixes and vertex shader works

* Added rudimentary texture and sampler support

* Basic preprocessor

* Added preprocessor if macros

* Pass tests and handle floats correctly

* Fix preprocessor if wrong precedence ordering when using macros
Refractor for the glsl parser
Partial primary expression parser

* Fix all clippy errors

* Cleanup

* Rollback formatting changes in lib.rs

* Move from travis to github actions (#58)

* Added github actions

* Remove travis

* Fixed clippy warnings

* Add the clippy check to ci

* Move workflows to .github

* Fix missing clippy

* Check constant types

A baby step towards #43

* Move tp src/proc/typifier, remove unneeded return

* Don't do pub(crate)

* Don't use crate::proc::UnexpectedConstantTypeError

Co-authored-by: Paul Kernfeld <paulkernfeld@gmail.com>

Fixes #31

A step towards #31