Summary:
SBT is the most common Scala buildsystem. This adds an extremely basic and
slightly horrible linter to check SBT's output for warnings and errors.
Test Plan:
Tested this with a Scala project I've been working on for some time.
It seemed relatively sane.
Reviewers: epriestley
Reviewed By: epriestley
CC: aran, Korvin
Differential Revision: https://secure.phabricator.com/D4064