v0.10 release

[Bromeon]

Remaining tasks:

• Remaining milestone issues/PRs
• Complete changelog [ ▶️ Rendered ]
• Double-check CI for publishing crates, possibly do a dry-run
• Add migration guide to book
• Publish a release candidate 0.10.0-rc.0 to allow for last-minute breaking patches
• Publish official release

I'd like to invite everyone to point out features/improvements they'd like to be part of v0.10.0.
In particular,

• If an issue/PR does not have the v0.10.0 milestone, it won't be implemented in the initial release.
• If an issue/PR has the breaking-change label and not the v0.10.0 milestone, it won't be implemented before v0.11.

Thanks to everyone for your efforts! 🙂

[chitoyuu]

I'd like to nominate the breaking parts of #601: Refactoring the NativeClass trait to make generic registration easier. The main roadblock here is fn class_name() -> &'static str, something rather hard to produce from a generic impl.

The class_name method is mostly used to produce error messages, which we can afford to make a bit slower. The static-ness does not seem to be useful except as an optimization.

I'm proposing that we separate the class name from the implementation types themselves, in the process also allowing users to change any class names at registration site. This is just a side-effect, but might be useful in "plugin"-style libraries, like gdnative-async, for avoiding name collisions with user types.

Static class names can still be supported through a separate trait (StaticallyNamed?), which could be used as a bound for the registration methods.

I can implement it this weekend if deemed useful.

[Bromeon]

I'd like to nominate the breaking parts of #601

Good with me, thanks a lot for volunteering! I answered directly in that issue.