Add help message for missing IndexMut impl with NLL#53830

Merged

bors merged 3 commits intorust-lang:masterfrom

davidtwco:issue-53228

Sep 7, 2018

Commits on Aug 30, 2018

Added InitLocation to encode Location or Local depending on source of Init
davidtwco
committed
Added help message for missing IndexMut impl.
davidtwco
committed
Omit 'missing IndexMut impl' suggestion when IndexMut is implemented.
davidtwco
committed