Show host information on setup issue screen

Summary: Ref T3780. Facebook has some environmental / itermittent stuff which would be easier to debug with host information on the setup issue screen.

Test Plan:
Checked both in-chrome and out-of-chrome versions of this screen, both looked reasonable.

{F56694}

Reviewers: wez, btrahan

Reviewed By: btrahan

CC: chad, aran

Maniphest Tasks: T3780

Differential Revision: https://secure.phabricator.com/D6842