Naive locking around build_requested for race condition (AUE-382)

Lock around build requested to avoid a scenario where builds that are requested
are not made.
cleanup
compensating for test names causes more problems than it solves, so skip it
use more intelligent lock params
Lock to the process context and unlock only once
File::Spec it up
Merge pull request #286 from jweible/AUE-382

Locking around build_requested for race condition (AUE-382)