test: Make job event waiting more explicit

Signed-off-by: Lewis Marshall <lewis@lmars.net>
Merge pull request #498 from flynn/refactor-job-event-waiting

test: Make job event waiting more explicit
WIP Run GitDeploySuite tests in parallel

Signed-off-by: Lewis Marshall <lewis@lmars.net>
test: Increase buildpack test HTTP request attempts

Signed-off-by: Lewis Marshall <lewis@lmars.net>
WIP Increase the job event wait timeout

Signed-off-by: Lewis Marshall <lewis@lmars.net>