Vulkan Generators

[tomadamatkinson]

Based on #574

The commit history here is longer than it needs to be as it includes some of the changes from the upcoming Vulkan Builders. This will hopefully be squashed and rebased before that PR is merged.

This PR adds the ability to generate Vulkan code fairly easily. A small framework on top of the Vulkan Headers generator allows for small fixed-purpose generators to be created with a minimal amount of code. In the future, I aim to add a Vulkan test framework using these generators.

For now, a single generator is used to create the get_structure_type_name helper. This helper is later used in the pNextChain builder which allows for an easy way to collect a pNext chain without dealing with tracking the chain itself. It will be used in the Instance and Device builder to allow samples to append extensions to the create structs dynamically.

See codegen/vulkan/readme.md for basic documentation on the generator itself.

[tomadamatkinson]

@asuessenbach resolved your comments and also renamed the generator and header along the same lines

[tomadamatkinson]

Fixed phantom line issue flagged by @asuessenbach. Merging on the original approval as no functional changes were made