Tracking issue for v2

[alejandro-vaz]

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

Relevant Open PRs

• feat: drop bincode entirely #426: awaiting review
• Reduce bloat from smallvec! in the inline case #424: awaiting author changes
• Added SmallVec::push_mut andSmallVec::insert_mut #406: stalled due to TaggedLen / set_len borrowing behavior
• Add an "allocator_api" feature #387: awaiting review
• Make RawSmallVec (and its fields) public only under feature = "internals". (v2) #348: awaiting review