Support OpenXR 1.1

[fredemmott]

• Handle python changes in v1.1
• Handle v1.0 extensions that are core in v1.1
• Check new structs in v1.1
• Check renamed structs and functions in v1.1
• Check all of the above in both 1.0 and 1.1 apps; make sure that structs/functions have the correct names based on if a 1.0 extension is being used or 1.1 core

As a lot of detail for the OpenXR update is gated behind Khronos-member-only 'internal MR' links, this likely either needs to be contributed by a Khronos member, or it appears to need to manually check against the 1300 lines of changes to xr.xml.

I'm very unlikely to do this until I personally want to trace a game that uses OpenXR v1.1, but will happily review pull requests.

[fredemmott]

Diffing the asciidoc may be a better way to go.

[fredemmott]

Much more detail here: https://registry.khronos.org/OpenXR/specs/1.1/html/xrspec.html#XR_VERSION_1_1