Add unstable VecDeque::rotate_{left|right}#56842

Merged

bors merged 3 commits intorust-lang:masterfrom

scottmcm:vecdeque-rotate

Dec 22, 2018

Commits on Dec 15, 2018

Add unstable VecDeque::rotate_{left|right}
scottmcm
committed

Commits on Dec 16, 2018

Add a note about why the unsafe is sound
scottmcm
committed

Commits on Dec 19, 2018

Add more VecDeque::rotate_{left|right} tests
scottmcm
committed