[Pkg-rust-maintainers] Bug#1090324: please upgrade to v0.15

[Peter Michael Green]

 > Please upgrade or separately provide newer branch v0.15.


Preliminary analysis

Quite a few removals listed in the upstream changelog, not clear how widely
used the removed APIs were though.

In terms of the upstream state of the rdeps, 0.14 still seems 
significantly more
prevalent than 0.15. So I don't think I'm going to drive this update at this
time, if another member of the rust team wants to do so they are welcome
to.

btm - Jonas's uses 0.15 upstream, debian is currently downpatching
rust-ahash - Jonas's Package still uses 0.14 upstream, but it's only a 
dev-dependency
rust-chumsky - rust team package, still uses 0.14 upstream
rust-dashmap - rust team package, still uses 0.14 upstream
rust-gix-hashtable - rust team package, still uses 0.14 upstream
rust-gix-index - rust team package, still uses 0.14 upstream
rust-hashlink - rust team package, new upstream uses 0.15 but it semver 
breaking, though the breakage looks pretty small.
rust-imara-diff - rust team package, still uses 0.14 upstream
rust-indexmap - rust team package, latest upstream uses 0.15 and is not 
semver breaking
rust-lru - rust team package, latest upstream uses 0.15 and is not 
semver breaking
rust-malachite-base - rust team package, still uses 0.14 upstream
rust-ordered-multimap - rust team package, still uses 0.14 upstream
rust-regalloc2 - Jonas's package, latest upstream uses 0.15 but is 
semver breaking
rust-rkyv - Rust team package, still uses 0.14 upstream
rust-rowan - Rust team package, still uses 0.14 upstream
rust-sqlx-core - Rust team package, still uses 0.14 upstream
rust-unicode-linebreak - Rust team package, latest upstream no longer 
depends on hashbrown, because it pre-generates code that was formerly 
generated using hashbrown..........
rust-wasmparser - Rust team package, latest upstream uses 0.15 but is 
semver breaking
rust-wasmtime (librust-cranelift-dev) - Jonas's package upstream still 
uses 0.14