Tracking issue for v2

[alejandro-vaz]

Information about the state of v2 will be here until a proper project/milestone is created

for the v2 spec, see the wiki

Relevant PRs

• Fix warnings #431: awaiting author changes
• Refactor v2: faster pop/reserve/retain_mut, modern Criterion benches, Miri-friendly tests + fmt in CI #396: not yet reopened after being reverted by Revert "Refactor v2: faster pop/reserve/retain_mut, modern Criterion benches, Miri-friendly tests + fmt in CI" #430 due to MSRV conflicts
• Implement defmt for v2 #391: postponed
• Add an "allocator_api" feature #387: proof of concept, awaiting author changes

2.0.0-alpha.13

Remaining:

• refactor lib.rs into modules #427
• 2.0.0-alpha.12..2.0.0-alpha.13 diff review

[alejandro-vaz]

let's migrate to proper milestones