Auto merge of #4743 - SimonSapin:default-members, r=matklad
authorbors <bors@rust-lang.org>
Wed, 29 Nov 2017 15:19:05 +0000 (15:19 +0000)
committerbors <bors@rust-lang.org>
Wed, 29 Nov 2017 15:19:05 +0000 (15:19 +0000)
Add a workspace.default-members config that overrides implied --all

Fixes #4507.


Trivial merge