Auto merge of #4564 - rust-lang:matklad-patch-2, r=alexcrichton
authorbors <bors@rust-lang.org>
Tue, 3 Oct 2017 10:17:41 +0000 (10:17 +0000)
committerbors <bors@rust-lang.org>
Tue, 3 Oct 2017 10:17:41 +0000 (10:17 +0000)
Describe E-mentor label in contributing.md


Trivial merge