Commit the ESAPI bindings if the ABI is stable

[hug-dev]

We should check if the ESAPI ABI is stable and if it is, commit inside the repository (or in tss-esapi-sys) the bindgen bindings that we currently generate everytime during compilation.

That has multiple advantages:

• make the compilation faster, without the bindgen step
• simplify the build script
• we would be able to use for docs.rs

[ionut-arm]

Going 180 on this, eh. I think the interface is stable, it's only library changes that might occur so this would make sense (but I do prefer creating a sys crate instead of just committing bindgened code).

[hug-dev]

but I do prefer creating a sys crate instead of just committing bindgened code

That would be part of the sys crate still! With only that file in it basically and means to do linking. I had this idea over re-reading this.

[Superhepper]

So we should use the latest version of tpm2-tss and only generate new bindings when a new version is released? Hrmm how much faster build times are we talking about?

[hug-dev]

Well I was hoping that since the TCG TSS 2.0 ESAPI is specified and stable (version 1.0), once the tpm2-tss implementation is compliant there would not be breaking changes with different versions of the implementation, unless the specification itself does a breaking change.
We would say that this crate is a wrapper around version 1.0. and work with all compliant implementations. But maybe it is more complicated than that!