Ben Gamari authored 8 years ago and Ben Gamari committed 8 years ago

This will allow us to split up Harbormaster output for the build and
test stages of validation.

Test Plan: `./validate --build-only && ./validate --testsuite-only`

Reviewers: thomie, hvr, austin

Differential Revision: https://phabricator.haskell.org/D2553

(cherry picked from commit 4d2b15d5)