Cross bindings

[YruamaLairba]

It add experimental bindings for arm and aarch64
Also update and improve the systool README

[YruamaLairba]

@Janonard i can add bindings for *-pc-windows-gnu targets but i don't know if it worth. Even if it's not identical to x86_64-pc-windows-msvc, it's fully compatible. The only noticeable difference is the signed/unsigned bindings on enum, which is irrelevant.

[JOOpdenhoevel]

I guess you can merge the gnu and msvc bindings. I used to be a little anxious about mixing bindings that aren't 100% identical, but given that the difference between signed and unsigned bindings is never relevant (and would even be annoying when you want to target both targets), I now think it's okay.

Also, does the existence of this PR mean that you're abandoning #64?

[YruamaLairba]

Also, does the existence of this PR mean that you're abandoning #64?

Yes. If i remember correctly, you forked it, did some change, and merged back to develop branch

[YruamaLairba]

@Janonard i updated the supported target section of README.md. I tried to separate binding concept from supported target concept. I'm not sure if my explanation are clear between supported target, usable target, experimental feature gated by experimental-targets

[JOOpdenhoevel]

I think you mean the right thing, but it isn't that clear yet: A target has three states: It may be missing from the sys-crate, it may be included but not supported, or it may be included and supported. The key difference is that for a supported target, there has to be maintainer who can trace problems regarding that target by executing a plugin with a certain host of that target. This has to be stated clearly and precisely.

[YruamaLairba]

I fixed explanation about target support requirement. For the rest, i don't know how to make it better. Maybe by presenting tables differently ? One difficulty in explanations is the "experimental-targets" feature, it doesn't really act as a gate for "unsupported but usable" targets. It may more clear if we rename this feature as "experimental-bindings", isn't it ?

[JOOpdenhoevel]

#80 is this better? If so, please pull develop and add your ARM bindings to Tier 2, so I can merge this PR!

[YruamaLairba]

i hope i fixed all my errors. Some of them was not detected by the automatic check

[JOOpdenhoevel]

Looks good!