sbt/sbt — pull request #1694 by jsuereth (2014-10-25 18:27:30+00:00)
Title: Fix the run logic so the mainClass setting is actually used when set.

This is one of those super hard to test scenarios where the "main class" being run is a from a different JAR (i.e. we'll never discover one). More importantly, the run task wasn't using the configured main class due to, what appears to be, a refactoring mixup we didn't catch during code review of the new select-main-class warning.

Review by @eed3si9n cc @fommil