Implement placement-in protocol for `BinaryHeap`#39062

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bors merged 2 commits intorust-lang:masterfrom

martinhath:placement-in-binaryheap

Jan 20, 2017

Commits on Jan 14, 2017

Add initial impl of placement-in for `BinaryHeap`
Martin Hafskjold Thoresen
committed

Commits on Jan 17, 2017

Fix BinaryHeap place by only constructing vec::PlaceBack once
Martin Hafskjold Thoresen
committed