Replace ElasticArray with SmallVec

[dvdplm]

The elastic-array crate is a fine piece of software but it'd be good to prefer crates that are commonly used in the ecosystem and likely to be well maintained. smallvec is at v1.0 and generally well-regarded.

Unfortunately as DBValue is part of the public API of kvdb, this is a breaking change so changing this implies annoying busy-work in consuming code.

[ordian]

Looks good, just minor grumbles

[ordian]

so it didn't work before on windows?

[dvdplm]

I honestly don't know how it could have worked; looks like the winapi went completely crazy with features at some point and didn't care much for semver.
The risks of updating dependencies with cargo upgrade...

[dvdplm]

@cheme I think it'd be good to have a somewhat coordinated release of trie-db before we can use this in eth/substrate. Can you help with that?

[cheme]

I think we should include paritytech/trie#46 and paritytech/trie#39. I would also like to have paritytech/trie#45, but I did not find time to review it (but it can be released later).
For the release it probably touch more or less all trie crates, there was a versioning shift with the bench crate (0.17 instead of 0.16), so I would propose to solve that by publishing 0.18 (skip a version).
I am currently off, but if needed I probably can find some time this evening to release it (IIRC there is also parity-common triehash crate to update after publishing 0.18 trie crates).

[dvdplm]

I would propose to solve that by publishing 0.18 (skip a version).

Sounds good.

Also: we'd need a 👍 on this PR to proceed. :)

[cheme]

👍