Rename examples to ash-examples

[MarijnS95]

Depends on #819

Dependabot complains that:

 the binary target name `examples` is forbidden, it conflicts with with cargo's build directory names

And fails to provide dependency upgrades for Rust code. Fix that by renaming the folder and crate to ash-examples.

[Ralith]

Weird, I don't think we actually have a binary target by that name, specifically? Probably a dependabot bug, but oh well.

[MarijnS95]

Weird, I don't think we actually have a binary target by that name, specifically? Probably a dependabot bug, but oh well.

Yeah, I found this suspicious as well but didn't read too much into it because folks like to
call shared objects "binary" as well. That said it should only emit an rlib?

EDIT: But it only matters for executables which have no extension on unix: target/debug/examples as exe would conflict with the folder created for target/debug/examples/{texture,triangle}. Seems unlikely that dependabot can do rigorous "does this crate actually produce a binary" tests based on various rules (autobins, [bin] name = "...", stuff existing in src/bin/, src/main.rs...).

Besides, dependabot is buggy in many more ways (failing to understand < vs <= ranges and bumping the latter to an inexistant version).